Post on 03-Feb-2016
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Definition:
The endocrine system is a control system of the body, which controls various functions of the human body through secretions known as hormones, secreted by the endocrine glands.Endocrine Glands:Endocrine glands are secretary tissues (glands) which secrete hormones directly into the blood stream. They are also called ductless glands. The study of endocrine glands is called endocrinology.
Important Endocrine Glands & Their Functions (secretions)
Following are the important endocrine glands of the human body.i) Pituitary Glandii) Hypothalamusiii) Thymusiv) Pineal v) Thyroidvi) Parathyroid vii) Adrenalviii) Pancreasix) Testesx) Ovaries
Pituitary Gland:The pituitary gland is a small bean-shaped reddish gray organ, located near the hypothalamus (forebrain). It produces at least nine hormones which perform following functions:Functions:- Responsible for normal skeletal growth, milk secretion in mammary glands.- Controls normal functioning of thyroid and adrenal glands- Stimulates the formation of the graffian follicles in the female ovary and development of spermatozoa in male.- Stimulate the contraction of the uterine muscles during the final stage of pregnancy- Control the amount of urine secreted by the kidney.HypothalamusThe hypothalamus is located immediately below the thalamus at the centre of the brain, and controls many automatic functions of the body.Function:The general functions of the hypothalamus are of extreme importance for the body, such as: - Pituitary gland regulation - Blood pressure regulation - Hunger and salt cravings - Feeding reflexes - Thirst - Body temperature regulation Thymus:The thymus gland, which is shaped like a pyramid, is a specialized organ of the human immune
system. It is also one of the important glands in the human body. It is a pinkish gray colored organ that is situated in the upper thoracic region, under the sternum or the breast bone.Function:The thymus gland is very active, when the individual is a child. It plays a crucial role in developing and improving a child's immunity system. The main function of the thymus gland is to produce and process lymphocytes or T cells.Pineal Gland:The pineal gland is a pine cone shaped gland of the endocrine system. A structure of the diencephalon of the brain, the pineal gland produces several important hormones including melatonin.Function:The pineal gland is involved in several functions of the body including:• Secretion of the Hormone Melatonin• Regulation of Endocrine Functions• Conversion of Nervous System Signals to Endocrine Signals• Causes Feeling of Sleepiness• Influences Sexual DevelopmentThyroid Gland:The thyroid gland is paired organ located in upper region of the neck in front of windpipe. It produces the hormone thyroxin (T4), Triiodothyronine (T3) and calcitonin.Functions:- Plays an important role in regulating the body's metabolism - The T4 and T3 hormones stimulate every tissue in the body to produce proteins and increase the amount of oxygen used by cells.- The calcitonin hormone works together with the parathyroid hormone to regulate calcium levels in the body.Parathyroid Gland:The parathyroid glands are embedded in the thyroid gland.Functions:- Controls the concentration of calcium (Ca ion) and phosphorus (phosphate) in the blood.- Stimulates the absorption of calcium and magnesium from the gut.- Increases tubular reabsorption of calcium, magnesium and hydrogen ions.Pancreas:The pancreas is located deep in the abdomen, sandwiched between the stomach and the spine. It produces two important hormones which are insulin and glucagon.Functions:- Insulin and glucagon are especially important for the maintenance of blood sugar, as insulin lowers the blood sugar and glucagon increases the blood sugar according to the body's needs.Adrenal Gland:The adrenal gland curve over the top of each kidney in abdomen. The important hormones secreted by adrenal gland are adrenaline, Aldosterone hormone, and cortisol.
Function:- Adrenal glands are responsible for secreting hormones essential for carrying out some important metabolic processes. Besides, they also help the body in dealing with physical and mental stress.
Ovaries:It is not only a reproductive organ which produces gametes but also make many steroidal hormones. The important ovary hormone is estrogen.Function:- Ovary hormones are responsible for female characteristics e.g. sound, body, bones, hair etc.Testes:It is not only a reproductive organ in males but also performs endocrine functions. Important hormone of testes is androgens.Function:Testes hormones are responsible for the development of male characteristics in male e.g. sound, bones, hairy body etc.
The excretory system is a system that removes excess, unnecessary or dangerous materials from an organism, so as to help maintain homeostasis within the organism and prevent damage to the body
Excretory Organs
1) Accessory Excretory Organs:i) Lungs: They remove or excrete Co2 as a waste product from the body.ii) Skin: Skin functions in excretion by sweating out waste products from the sweat glandsiii) Liver: The liver excretes cholesterol, steroid hormones, certain vitamins and drugs through the bile and also urea, ammonia, amino acids etc.2) Main Excretory Organi) Kidneys: Excretes waste products in the form of urine
Structure & Working Of Kidney:External Structure:i) Renal Artery: The renal artery enters the kidney and brings oxygenated blood carrying toxic nitrogenous wastes into the kidneys.ii) Renal Vein: The renal vein drains away deoxygenated blood which is free of toxic substancesiii) Ureter: The ureter, a tube, runs from each kidney downwards into the lower part of the abdomen connecting each kidney to the urinary bladder. Its function is to transport the urine from the kidneys to the urinary bladder.iv) Urinary Bladder: This is a large muscular storage sac that collects urine from both the kidneys through the ureters.v) Urethra: This is a short muscular tube that carries urine at intervals from the urinary bladder to the outside.Internal Structurei) Renal Cortex: This is the outer pale red colored layer.ii) Renal Medulla: This forms the inner dark red zoneiii) Renal Pelvis: This is a large funnel-shaped region behind the renal medulla.iv) Nephrons: These are structural and functional microscopic filtering units of the kidney. There are more than 1,250,000 nephrons in each kidney.Microscopic Structure of a Nephron
i) Malpighian Corpuscle: This consists of two parts:a) Bowman's Capsule: This is a cup - shaped structure which is double walled in the hollow of which is a network of capillaries called the glomerulusb) Glomerulus: This is a knotted mass of blood capillaries formed by the afferent arteriole (incoming) and the efferent arteriole (outgoing).ii) Renal Tubule: This further consists ofa) Proximal Convoluted Tubule: This is the region behind the Bowman's capsule and consists of a coiled tube that descends to form the Henle's loop.b) Henle's loop: This is continuous with the proximal convoluted tubule and is U-shaped having a narrow descending limb and a thick ascending limbc) Distal Convoluted Tubule: This is another coiled and twisted tubule that continues from the ascending limb of loop of Henle found in the renal cortex.iii) Collecting Tubule: The distal convoluted tubule continues to form the collecting tubule.iv) Collecting Ducts: Several collecting tubules fuse to form large collecting ducts which pass downwards from the cortex to the medulla region.Working Of The Kidney:• The nephron is the kidney’s functional unit.• In its first section renal corpuscles filtration occurs.• As fluid, small molecules and blood are filtered from glomerulus capillaries.• The filtered material called filtrate is captured in Bowman’s capsules.• Filtrate then enters the proximal convoluted tubule.• Reabsorption of important molecules and ions from the filtrate into the blood occurs here.• These include glucose, amino acids, vitamins, water, sodium, potassium, chloride and bicarbonates.• Filtrate then enters into Loop of Henle which consists of descending limb and ascending limb.• In descending limb only water is reabsorbed and in ascending limb only salt is reabsorbed.• In distal convoluted tubule secretion occurs. Ammonia, hydrogen ions, uric acid are secreted from blood vessels into the distal tubule. • As result concentrated fluid called urine is produced which enters into collecting.Composition Of Urine:The urine is composed of following substances:i) Water: 95%ii) Dissolved Substances: 5%a. Urea: 2%b. Uric Acid and other ammonium compound: 1%c. Organic and inorganic salts: 2%iii) Inorganic constituentsiv) Nitrogenous Constituentsv) Other Constituents.Functions Of Kidney:1) Excretory• Excrete waste products especially nitrogenous substances• Eliminates drugs and toxic substances2) Synthetic• Synthesis ammonia and Hippuric acid3) Endocrine
• Secretes Renin4) Regulatory• Maintains - pH balance- Sodium ion, potassium ion and electrolyte balance- Osmotic pressure in blood- Water balance, extra fluid volume- Blood pressure
The largest gland of the body: LiverThe largest organ of the body: SkinThe longest bone of the body: FemurThe total number of bones in the body: 206The hardest bone of the body: ToothThe smallest bone of the body: StapesTotal number of muscles in the body: 600The filter of the body: KidneyThe pump of the Body: HeartTotal number of bones in vertebral column: 33The normal body temperature: 98.4 F (37 C)The normal respiratory rate of the Body: 16-18 per minThe total volume of blood in body: 4-5 litresTotal number of bones in face: 14Vascular connection between foetus and uterus: Placenta
Branches Of Biology:
i) Zoology: Zoology is that branch of biology which deals with the study of animals.ii) Botany: Botany is that branch of biology which deals with the study of plants.iii) Microbiology: It is the branch of biology which deals with the study of microorganisms such as viruses, bacteria etc.iv) Morphology: It deals with the shape and structure of living organisms.v) Histology: It is the microscopic study of tissues of plants and animals.vi) Cytology: It deals with the structure of cell and organelles present inside the cell.vii) Physiology: It deals with the study of functions of different parts of plants and animals.viii) Ecology: It is the science of ecosystem and explains the relationship between organisms and their environment.ix) Taxonomy: It deals with the naming and classification of organisms.x) Genetics: It deals with the study of heredity and variations.xi) Biotechnology: It deals with the application of biological processes.xii) Hematology: Study of blood and its constituent cells.xiii) Geology: Study of features and properties of earth and its constituents rocks.
Characteristics Of Living Organisms:
Following are the main characteristics of living beings which are not present in non-living organisms.
i) Metabolismii) Growthiii) Irritabilityiv) Reproductionv) Movementvi) Nutritionvii) Respirationviii) Excretion
Virus:
• Viruses are the micro-organisms which are strict or obligate parasites of animals or plant cells.• Many of the viruses are also parasites on bacteria.• A large number of viruses cause diseases in plants and animals.Characteristics Of Virus:• A virus consists of two components, a protein coat and a core of nucleic acid which is either DNA or RNA.• DNA viruses are called adenoviruses and RNA viruses are called retroviruses.• The shape of a virus is due to its protein coat.• Viruses are of many shapes i.e. rods, spherical, hexagonal or icosahedral.• Sometimes their shape is complicated.• Virus replicate inside a living cell and many viruses are synthesized along with their protein coats and nucleic acid.• The nucleic acid contains instructions for the shape of the virus.Diseases Caused By viruses:i) Polioii) AIDSiii) Smallpoxiv) Measlesv) Hepatitis
Bacteria:
Characteristics Of Bacteria:
• Bacteria are unicellular prokaryotic organisms which generally divide by transverse binary fission.• They possess rigid cell walls and act as pathogens• Nucleus is not well organised• No definite chloroplast, chlorophyll is dissolved in chromoplasm.• There are three forms of bacteria which are:i) Round called Cocciii) Rod like called Bacilliiii) Spiral called SpirrilaClassification Of Bactria According To Mode Of Nutrition:According to mode of nutrition, there are three types of Bactria:
a) Parasitic:• Devoid of chlorophyll• Are heterotrophic and get food from living animals and plantsb) Saprophytic• Lack chlorophyll hence cannot prepare their own food.• Get food from dead organic remainsc) Autotrophic• Contain chlorophyll• Can synthesis food by photosynthesis• Few get their food by chemosynthesisReproduction In Bacteria:i) Vegetative: By Binary Fissionii) Asexual: By Formation of Endosporesiii) Sexual: By Conjugation
Cell:
Definition:The smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane.ORThe cell is the functional basic unit of life. It was discovered by Robert Hooke and is the functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life.Cell Structure And Functions (Plant & Animal Cell)1. Cell wall- Most commonly found in plant cells- Controls turgidity- Extracellular structure surrounding plasma membrane- Primary cell wall: extremely elastic- Secondary cell wall: forms around primary cell wall after growth is complete2. Plasma membrane- Outer membrane of cell that controls cellular traffic- Contains proteins (left, gray) that span through the membrane and allow passage of materials- Proteins are surrounded by a phospholipid bi-layer.3. Protoplasm-colourless, semitransparent, viscous granular fluid present inside the cell is called as protoplasm.-colloidal in nature and considered as physical basis of life.-exhibits the active streaming movement called cyclosis -it consists of water, protein, lipid or fats, carbohydrates, enzymes, salts, nucleic acid in a fixed proportion.-it is divided into Nucleus and Cytoplasm4. CytoplasmProtoplasm outside the nucleus is called cytoplasm,all the organelles are present in the cytoplasm like;i) Endoplasmic reticulum
-Tubular network fused to nuclear membrane- Goes through cytoplasm onto cell membrane- Stores, separates, and serves as cell's transport system- Smooth type: lacks ribosome’s- Rough type (pictured): ribosome’s embedded in surface
ii) Golgi apparatus- - Composed of numerous layers forming a sac- Works as the distribution and shipping department of the cell’s chemical product.iii) Lissome- - Digestive 'plant' for proteins, lipids, and carbohydrates- Transports undigested material to cell membrane for removal- Vary in shape depending on process being carried out- Cell breaks down if lissome explodesiv) Mitochondria- Second largest organelle with unique genetic structure- Double-layered outer membrane with inner folds called cristae- Energy-producing chemical reactions take place on cristae- Controls level of water and other materials in cell- Recycles and decomposes proteins, fats, and carbohydrates, and forms ureav) Ribosome’s- Each cell contains thousands- Miniature 'protein factories'- Composes 25% of cell's mass- Stationary type: embedded in rough endoplasmic reticulum- Mobile type: injects proteins directly into cytoplasmvi) Vacuoles- Membrane-bound sacs for storage, digestion, and waste removal- Contains water solution- Contractile vacuoles for water removal (in unicellular organisms)vii) Chloroplasts- A plastid usually found in plant cells- Contain green chlorophyll where photosynthesis takes placeviii) Cytoskeleton- Composed of microtubules- Supports cell and provides shape- Aids movement of materials in and out of cellsix) Centrioles- Paired cylindrical organelles near nucleus- Composed of nine tubes, each with three tubules- Involved in cellular division- Lie at right angles to each other5. Nucleus:-Control centre of the cell-Serves as information processing and administrative centre of the cell-Performs the following major functions:
a) stores the cell’s hereditary material, or DNAb) coordinates the activities of the cell, which includes growth, metabolism, protein synthesis, and reproduction or cell division.i) Nuclear membrane- Surrounds nucleus- Composed of two layers- Numerous openings for nuclear trafficii) Nucleolus- Spherical shape- Visible when cell is not dividing- Contains RNA for protein manufactureiii) Chromosomes- Usually in the form of chromatin- Contains genetic information- Composed of DNA- Thicken for cellular division- Set number per species (i.e. 23 pairs for human)
Difference Between Animal And Plant Cell:
1) Cell Wall OR Cell Membrane- The outer boundary of plant cells is known as the cell wall, which is mainly composed of cellulose.- It helps the plant cell to maintain its shape.- The cell wall is absent in animal cell.- In animal cell the outer covering is known as cell membrane which is composed of lipid bilayer, proteins and carbohydrates.2) Plastids- Plants cells also contain organelles which are known as plastids.- The most common type of plastid is the chloroplast which contains chlorophyll.- These organelles or plastids are totally absent in animal cell.3) Vacuole- The main difference between the vacuole of animal and plants is their size.- The vacuole of plant cell is much bigger than that of animal cells.4) Centrosomes- In animal cells centrosomes are present, which are responsible for making some protein fibres which help in movement of chromosomes during division of cells.- Centrioles are absent in the plant cells.5) Lysosome- Lysosomes are not evident in plants while they are prominent in animal cells.
Cell Division:
The process in which the cells divide and replicate. This process is the basis for growth and replication. There are two main types of cell division, which are as under:
1) Mitosis2) Meiosis
Mitosis:
A type of cell division in which a cell divides into two identical daughter cells each having same number of chromosomes as that of parent cell.Stages Of Mitosis:There are four stages of mitosis, which are as under:i) Prophaseii) Metaphaseiii) Anaphaseiv) Telophasei) Prophase:- Prophase is the first phase of mitosis.- Chromatin material condenses and becomes visible- The nucleolus of the cell disappears- The nuclear membrane also disappears- Centrioles begin to move opposite ends of the cellii) Metaphase:- Metaphase is the second stage of mitosis.- Chromosomes line up in the centre of the cell, separate and become a pair of identical chromosomes.- The chromatids become uncoiled and apart from each other.iii) Anaphase:- It is the third phase of mitosis.- During this phase each set of chromosomes move towards the opposite end of the cell.iv) Telophase:- The fourth phase of mitosis is known as Telophase.- During this phase spindle fibres disappear.- Nuclear membrane appears- Cell divides into two daughter cells- Nucleolus re-appear- The chromosomes disperse and are no longer visible.Significance Of Mitosis:1. Growth: The number of cells within an organism increases by mitosis and this is the basis of growth in multicellular organisms.2. Cell Replacement: Cells are constantly sloughed off, dying and being replaced by new ones in the skin and digestive tract. When damaged tissues are repaired, the new cells must be exact copies of the cells being replaced so as to retain normal function of cells.3. Regeneration: Some animals can regenerate parts of the body, and productions of new cells are achieved by mitosis.4.Vegetative Reproduction: Some plants produce offspring which are genetically similar to themselves. These offspring are called clones.Meiosis:
A type of cell division in a cell divides into four daughter cells with having half number of chromosomes as compared to parent cell.
Characteristics Of Meiosis:
• Takes place in sexual reproduction at the time of formation of male and female gametes• In animals it takes place during the formation of sperms and ova while in plants during spore formation• Diploid cells reduce to haploid cells• Consists of two consecutive divisions• First division is reductional or meiotic and the second is simple mitotic division.Stages Of Meiotic Division:i) Prophase Iii) Metaphase Iiii) Anaphase Iiv) Telophase Iv) Prophase IIvi) Metaphase IIvii) Anaphase IIviii) Telophase IIProphase I:Prophase I consists of 5 sub stages, these are:a. Leptotene- Nucleus increases in size- Chromosomes become long and uncoiled threads- They become more visibleb. Zygotene- Homologue (similar) chromosomes attract each other and form pairs.- This process is called synapsesc. Pachytene- Chromosomes become condensed due to widening of coils- They form chiasmata i.e. cross each other in double nature or bivalents.d. Diplotene- Homologous chromosomes go apart from each other except at chiasmata- Chromosomes become more short and thickere. Diakinesis- The bivalents become more apart.- Chromosomes become deeply stained- Nucleolus and nuclear membrane disappear and spindles become distinctMetaphase I:- Chromosomes now rearrange themselves in an equatorial line- Spindles attach to the centrosome of the chromosomesAnaphase I:- Spindles start to contract- Split the tetrahedral chromosomes into two chromatids and drag them to opposite poles- Here the reduction takes place.
Telophase I:- Spitted chromosomes reach to opposite poles- Nucleolus and nuclear membrane reappear- At the end of Telophase I, prophase II starts.Prophase II:- Chromatin network breaks into bivalent chromosomes- Nuclear membrane and nucleolus disappear and spindles start to reappearMetaphase II:- Bivalent chromosomes rearrange themselves at equator- Spindles attach to the centrosomes of each chromosomeAnaphase II:- Spindles contract and split the chromosomes longitudinally into two chromatids- Each chromatid travel to opposite poleTelophase II:- Each chromatid reach to the opposite pole- Spindles disappear and nuclear membrane and nucleoli reappear- As a result 4 nuclei are formedSignificance Of Meiosis:- To allow trait inheritance in offspring- To maintain diploid number in each generation- To ensure the production of haploid gametes in sexual reproduction- To produce genetic variations among offspring
Classification Of Plants:
Plants are those organisms which contain chlorophyll and synthesize their own food through photosynthesis. Plants are divided into:
1) Flowering Plants OR Phanerogams2) Non-Flowering Plants OR CryptogamsFlowering Plants: Flowering plants are those plants which contain seed. These are known as Phanerogams. They are further subdivided into:i) Gymnospermsii) AngiospermsGymnosperms:Gymnosperms are those flowering plants which contain naked and unprotected seeds.Examples: Pine, Fir, Cedar, Spruce and Cypress etc.Angiosperms:Angiosperms are those flowering plants whose seeds are protected by a fruit or seed pod.Examples: Grass, Crops, Vegetables, Fruits and weeds.Non-Flowering Plants:Non-Flowering plants are also known as cryptogams. These are the plants which do not have seed or in other words they are seedless. Following are the main characteristics of these plants:- They reproduce by spores- They have long life
- They have no long fibres- They cannot grow to greater size- They generally have simple structure, except ferns.Examples: Moses, Ferns, Algae.
Flower & Its Parts:
The flower is the reproductive part of the plant. It is mainly concerned with formation of seeds. It is regarded as the modified shoot for the purpose of reproduction.
Parts Of Flower:
A typical flower consists of a short axis known as the thalamus, on which floral leaves are inserted in four distinct whorls, which are as under:i) Calyxii) Corollaiii) Androeciumiv) GynaeciumCalyx:Calyx is the outermost whorl of floral leaves called sepals. The sepals can be defined as the green and leaf like structures which are mainly concerned with the protective function.Corolla:Corolla is the second whorl of floral leaves called petals. The petals are beautifully coloured which are responsible for the attraction to the insects towards them.Androecium:The third whorl of the leaves consists of stamens. It is considered as the male part of the flower.Gynaecium:Gynaecium is the inner most whorl of the floral leaves called carpels. It is considered as the female part of the flower.
Parts Of Plants:
i) Ginger: Modified Stem (rhizome) and it is also a root.
ii) Cinnamon: Bark of stemiii) Radish: Rootiv) Potato: Stem (tuber)v) Peanut: Seedvi) Saffron: Stigma/flowervii) Almond: Fruitviii) Chillies: Fruitix) Spinach: Leavesx) Tomato: Fruitxi) Turnip: Rootxii) Carrot: Rootxiii) Cucumber: Fruit
Photosynthesis:
Definition:
Photosynthesis is a process in which plants manufacture their food (simple carbohydrates) in the presence of chlorophyll and sunlight by the combination of carbon dioxide and water.Raw Material For Photosynthesis:i) Carbon dioxide: Taken from airii) Water: Absorbed by roots from soiliii) Sunlight: From Suniv) Chlorophyll: green pigment present in leavesBy-Products Of Photosynthesis:i) Carbohydrates (simple sugar): used by plants as a food material and excess of it is converted into starchii) Oxygen: Released into airImportance Of Photosynthesis:i) Major process of food production in plantsii) Utilization of CO2 of the atmosphere and liberation of oxygeniii) Important in reducing CO2 of the atmosphere which is dangerous for the human beings as well as animal health.
Pollination:
Definition:Pollination is the phenomenon of transfer of pollen from male reproductive organ (anther) to female reproductive organ (stigma) in flowering plants through biological or physical agency.Types Of pollination:There are two types of Pollinationi) Self-Pollination:In this type of pollination pollens are transferred to the stigma in the same flower. Some plants are by nature self-pollinated as wheat and grasses.ii) Cross Pollination:In this type the pollen grains are transferred from the anther of one flower to the stigma of another flower. The cross pollination is considered and advantageous to the plant as the seeds produced by cross-pollination are usually greater in number and the plant germinated from them are superior in vigour, height and weight.Vehicles For Pollination:Vehicles for pollination are animals, water, wind and insects. Therefore cross pollination may be:a) Entomophily-by insectsb) Anemophily-by windc) Hydrophily-by waterd) Zoophily-by animals
Importance Of Pollination:• Vital process for reproduction in plants
• Reproduction is carried out by reproductory organs of plants due to pollination• It is the process by which seeds are produced.
Fertilization:
The fusion of male and female gametes is called fertilization.Types Of Fertilization:Following are the major types of fertilization:i) External Fertilizationii) Internal Fertilizationiii) Self-Fertilizationiv) Cross-FertilizationExternal Fertilization:• This type of fertilization is generally observed I simple aquatic animals.• In such animals both ova and sperms are released into the water where fertilization occurs.• In terms of evolution external fertilization is of primitive type and is not better biologically as compared to internal fertilization.Internal Fertilization:• In the internal fertilization the females keep ova inside their bodies and males deposit sperms within the tube of reproductive tacts of females.• For all land animals internal fertilization is almost must because sperms are quickly killed by dehydration.• In terms of evolution internal fertilization is highly evolved and much better biologically as compared to external fertilization.Self-Fertilization:• Self-fertilization occurs within the same animal.• It is that fertilization in which sperms are used by the ovaries of same animal e.g. TapewormCross-fertilization:• Cross-fertilization is the process in which sperms of one animal are transferred into the body of another animal e.g. Earthworm.
Animals:
Types Of Animals:
i) Invertebrates: Animals having no backbone or vertebral column.ii) Vertebrates: Animals with backbone or vertebral column.Classification Of Invertebrates:The invertebrates are classified into following categories:i) Phylum Protozoaii) Phylum Porifera iii) Phylum Coelentrataiv) Phylum Platyhelminthesv) Phylum Nematode
vi) Phylum Annelidavii) Phylum Molluscaviii) Phylum Arthropodaix) Phylum EchinodermataFollowing are the most common examples of invertebrate animals with their relative phyla:- Euglena: Phylum Protozoa- Paramecium: Phylum Protozoa- Amoeba: Phylum Protozoa- Sponges: Phylum Porifera- Hydra: Phylum Coelentrata- Jelly fish: Phylum Coelentrata- Tapeworm: Phylum Platyhelminthes- Ascaris: Phylum Nematode- Hookworm: Phylum Nematode- Filaria: Phylum Nematode- Snails: Phylum Mollusca- Squids: Phylum Mollusca- Cockroach: Phylum Arthropoda- Honey bee: Phylum Arthropoda- Mosquito: Phylum Arthropoda- Butter fly: Phylum ArthropodaClassification Of Vertebrates:Vertebrates have been divided into following five major classes:i) Fishesii) Amphibiansiii) Reptilianiv) Birdsv) MammalsSome Animals & Their Location:i) Blue whale: Found in all oceansii) Panda: Chinaiii) Dolphin: In seasiv) Porpoises: v) Kangaroo: Australiavi) Snow Leopard: Central Asiavii) Yak: Central Asiaviii) Llama: South Americaix) Ibex: Wild mountain goatx) Cobra: South Asiaxi) Alligator: N.Americaxii) Tortoise: Waterxiii) Rattle Snake: Americaxiv) Lizards: xv) Crocodiles:xvi) Ostrich: Deserts Of Africaxvii) Penguin: Antarctic Region
xviii) Kiwi: New Zealandxix) Rhea: South Americaxx) Emu: Australiaxxi) Shark: Found in all oceansxxii) Trout: Fresh water fishxxiii) Cod: Scavenger:Scavengers are the animals that ‘Clean up’ after the other animals by consuming their leavings and sometimes prey on sick or dying animals or consume dead bodies. Scavengers are also called detritus feeders. Vultures, coyotes, jackals, hyenas and wild dogs are scavengers which eat the left over prey or dead bodies of hunted animals.
Ecosystem:
Definition:A natural of habitat or system where living organisms and physical components of their environment interact with one another and exchange materials so as to achieve a functional stability is called an ecosystem.Characteristics Of Ecosystem:• An ecosystem is a basic unit of ecology of living organisms.• An ecosystem may be natural like a pond, lake, stream, river, ocean or a forest.• It may also be artificial like an Aquarian, an artificial pond or an agricultural field.• A pond is an excellent example of a small ecosystem to demonstrate interrelationship between abiotic and biotic component of the ecosystem.Components Of Ecosystem:i) Abiotic Components Of Ecosystem.Following are the abiotic components of ecosystem.a. Lightb. Temperaturec. Waterd. Atmosphere and winde. Firef. Soilg. Topographyh. Gravityi. Inorganic nutrientsii) Biotic Factors.Following are the biotic components of ecosystem.a. Producers: Green Plantsb. Consumers: Animals and Manc. Decomposers and reducers: Bacteria, fungiTypes Of Ecosystem:There are two main types of ecosystem:i) Terrestrial Ecosystem: it includes Forest and Desert Ecosystemii) Aquatic Ecosystem: it includes small pool, a pond, stream, river, lake and an oceanic ecosystem
Heredity:
Terminology Of Genetics:Gene:The basic unit of hereditary material which is responsible for development of a trait.Alleles:Alternatives forms of genes are called alleles, e.g. tall versus dwarf.Dominant:The dominant alleles are those traits which show complete expression even in heterozygous state. Dominant alleles dominate the recessive alleles in heterozygous state.Recessive:Recessive alleles or traits are those which fail to express themselves in heterozygous state. For example r and y are recessive alleles for wrinkle and green seeds.Homozygous:Homozygous is a condition in which an individual possess similar alleles for a particular trait. For example TT for tallness and tt for dwarfness.Heterozygous:Heterozygous is a condition in which an individual possess dissimilar alleles for a particular trait. For example Tt for tallness.Genotype:Genetic make of an organism is called genotype. Phenotype:External appearance or expression of genotype is called phenotype. For example, roundness, wrinkleness of seeds and tall or dwarf plants represent different phenotype.
Gene:
Definition:The fundamental unit of heredity, formed as a sequence of bases in DNA.Characteristics Of Genes:• Each gene has a definite position at the chromosome and may occur as alleles.• The name gene was introduced by Johannsen in 1909 and the structure of DNA was elaborated by Watson and Crick in 1953.• Genes determine all the structural and functional characters of an individual, like eye colour, skin colour, height, weight, blood group, hair, intelligence, temperament and all others.• The characters from one generation to other are taken by genes. • They sometimes change through the process of mutation. This gives variety in characters.• The accurate structure of the proteins and enzymes in the body is determined by genes.
Chromosomes:
A chromosome is a rod-like portion of the chromatin of a cell nucleus, performing an important part in meiotic cell division, and in the transmission of heredity characteristics. Normally they are constant in number for any species; there are 22 pairs of chromosomes and two sex chromosomes in the human.Types Of Chromosomes: in higher animals and plants, there are two fundamental types of
chromosomes, which are classified on the basis of sex determination these are:i) Autosomesii) Sex Chromosomes:Autosomes:These are paired somatic chromosomes that play no part in sex determination of organisms. These chromosomes are similar in males and females.\Sex Chromosomes:The chromosomes that determine sex in organisms are called sex chromosomes. There are two types of sex chromosomes.a) X- chromosomeb) Y- Chromosome
Genetic Engineering:
The deliberate modification of the characteristics of an organism by manipulating its genetic material.ORScientific alteration of the structure of genetic material in a living organism. It involves the production and use of recombinant DNA and has been employed to create bacteria that synthesize insulin and other human proteins.Significance Of Genetic Engineering:i) To Cure the genetic disordersHeredity diseases can possibly be treated by this technique by transplanting normal genes in the place of abnormal or diseased genes.ii) To Prepare Better CropsCrops with desired characteristics could possibly be produced by introducing desired genes.iii) To Get Better Breeds Of AnimalsLike plants better breeds of animals can also be produced by the introduction of recombinant DNA.iv) InterferonInterferons are effectively used in the treatment of Hepatitis of A & B.v) InsulinHuman insulin is being produced by genetic engineering to treat diabetesvi) VaccinesGenetic engineering has also helped in the production of vaccines which are used for controlling and treating viral diseases.
Biotechnology:
The exploitation of biological processes for industrial and other purposes, esp. the genetic manipulation of microorganisms for the production of antibiotics, hormones, etc.
ORBiotechnology is the use of living organisms (especially microorganisms) in industrial, agricultural, medical and other technological applications.Importance Of Biotechnology:
i) To increases productionii) To introduce improved quality of seeds and plantsiii) To introduce plants resistant to disease and insect pestsiv) To introduce verities suited to particular climates and soils.v) To introduce verities resistant to lodgingvi) To improve nutritional value of cropsvii) To save rare varieties of plants by rapid clonal propagation for breeders to use in future.
Teeth:
The humans have two sets of teeth one replaced by the second. The primary set or milk or deciduous teeth are 20 in number while there are 32 permanent teeth in adults.1. In children there are 20 deciduous or milk teeth. These areIncisor: 2 pair × 2= 8Canine: 1 pair × 2= 4Premolars: 2 pair× 2=82. In adults there are 32 permanent teeth. In each jaw on each side there are:Incisors: 2 pair × 2=8Canines: 1 pair × 2=4Premolars: 2 pair × 2=8Molars: 3 pair × 2= 12Incisors:The central front teeth are called incisors. There are four in upper jaw and four in lower jaw.Canines:The pointed, dark colored teeth on either side of the incisors are canines. 2 in upper jaw and 2 in lower jaw.Premolars:These are bi-cusped teeth after the canines. There are 8 premolars. 4 in the upper jaw and 4 in the lower.Molars:There are 12 molars, 6 in the upper jaw and 6 in the lower jaw.Structure Of Teeth:Each tooth consists of a crown which is the visible part and the root, which anchors it in sockets in the jaw. A tooth consists mainly of dentine. The crown is coated with even harder enamel, while the root is covered with cementurn to help another it in the jaw. Inside each tooth, there is a cavity full of pulp, carrying nerves and the tooth’s blood and eats through the dentine to the pulp when the decay reaches the pulp, pain and inflammation follows and tooth may die.A nerve, an artery, a vein and lymph duct enters the pulp cavity through the root canal. The nerves give sensation of hot and cold.
Antibody:
Antibody is a protein produced by white blood cells that help to destroy bacteria. Antibodies react with the antigens and inactivate or destroy them. A large number of antibodies are produced in blood which are targeted against various types of antigens. Antigens are foreign molecules, cells, bacteria, viruses or fungi which enter the body usually a disease causing
microorganisms. Antibodies are the integral part of the defence mechanism of human body. They are also involved in immunity against disease.
Hemophilia:
• It is a disease in which the peron have prolonged blood clotting time resulting in excessive bleeding fron injury.• It is due to the deficiency of vitamin K.• It is a semilethal disease controlled by recessive gene.• It is less common in women than in men.
Important Facts About Human Physiology:
The largest gland of the body: LiverThe largest organ of the body: SkinThe longest bone of the body: FemurThe total number of bones in the body: 206\The hardest bone of the body: ToothThe smallest bone of the body: StapesTotal number of muscles in the body: 600The filter of the body: KidneyThe pump of the Body: HeartTotal number of bones in vertebral column: 33The normal body temperature: 98.4 F (37 C)The normal respiratory rate of the Body: 16-18 per minThe total volume of blood in body: 4-5 litresTotal number of bones in face: 14Vascular connection between foetus and uterus: Placenta
Brain:
Human brain is contained in skull. It has three major parts.i) The Cereberum ot bigger brainii) The Cerebellum or Smaller brainiii) Medulla Oblongata or hind brainThe cereberum constitutes the major volume of brain. It consists of two large masses of nervous material known as cereberal hemispheres. Human consciousness, thought, emotions, sight, will, hearing, sensation of pain, memory and speech are centere in the creberum. Some parts of it also control motor nerves, operating the arms and legs.The cerebellum or the smaller brain is related with the coordination of action of nerves and muscles. In this way movements of body are manged. Medulla or hind brain contains the centres for reflex actions in addition to automatic movements such as breathing and walking.Reflex Action:
- Reflex actions are the responsed to environmental changes both internal and external and are immediate or automatic and are without intervention of will.
- These reflexes amy be simple or conditioned e.g. watering of mouth on seeing or smelling of food.- Simple reflexes are inborn, inherited or unlearnt responses to stimuli.- The structural and functional basis of simple reflex is called reflex arc.- Impulses are carried from receprtors to sensory neurons to CNS from where they are passed on via motor neurons to the effectors for necessary response.
Thermoplastics:
Substances (esp. synthetic resins) that become plastic on heating and harden on cooling and are able to repeat these processesORA type of plastic that can be softened by heat, hardened by cooling, and then softened by heat over and over again.Properties of Thermoplastics:Thermoplastics have wide ranging properties. - They can be very much like rubber, or as strong as aluminium. - are light in weight, - Can withstand temperature extremes of up to 600 F, while others retain their properties at -100 F. Some - Thermoplastic materials have no known solvents at room temperature. - Most thermoplastic materials are excellent insulators, both electrical and thermal. - Are recyclable materials that are used frequently today to create objects such as foam cups, polyethylene squeeze bottles, acrylic lenses and safety helmets.- In general the combination of light weight, high strength, and low processing costs make thermoplastics well suited to many applications.Uses:- They are useful for a variety of applications, including consumer goods, machine parts, medical equipment and packaging and storage materials.Examples:• PVC/Vinyl• Polystyrene• Polyethylene• Cellulose Acetate• PTFE/Teflon• Nylon/Polyamide• PolyesterSynthetic Polymers:
Polymers are composed of very large molecules (macromolecules) formed by linking together many smaller, more simple units called monomers. There can be as few as five or as many as several thousand monomers units in a polymer. There are a large number of synthetic polymers prepared and in use. Some of these are polyamides(nylon), polyethylene, propylene, polyvinylchloride, synthetic rubber, cellulose acetate, cellulose nitrate and silicones.
Blood:
Blood is vital connective tissue (fluid) consisting of fluid portion i.e. plasma, in which are suspended the formed elements i.e. RBCs, WBCs, and the platelets, along with other particles.Blood is opaque, alkaline and appears scarlet red when taken from arteries and purplish from veins. The difference in colour is due to its oxygen content.Composition Of Blood:The human blood is composed of:1) Formed ElementsFormed elements of blood are:• RBCs• WBCs• Platelets2) Plasma;The fluid portion of blood is known as the plasma. It is composed of:• Water: 91 to 92%• Solids: 8 to 9%The solids are again classified as inorganic and organic:Inorganic solids include:• Sodium• Magnesium• Iron• Potassium• Phosphorous• Copper While organic substances are:i) Proteins:• Serum Albumin• Serum Globulin• Prothrombin• Fibrinogenii) Non-Protein Nitrogenous Substances:e.g. urea, uric acid, xanthine, creatinine, NH3 and amino acids etc.iii) Fats:Like: Natural fats, phospholipids, cholesterol etc.iv) Carbohydrates Like: Glucosev) Other Substances:These include internal secretions, antibodies, enzymes i.e. amylase, protease and lipase etc.Functions Of Blood:• To transport oxygen and nutrients from the lungs and intestines respectively to all cells in your body.• To fight pathogens and kill bacteria and other microbes.• To keep our core body temperature stable.• To help heal and clot wounds.
Excretory System:
The excretory system is a system that removes excess, unnecessary or dangerous materials from an organism, so as to help maintain homeostasis within the organism and prevent damage to the body Excretory Organs1) Accessory Excretory Organs:i) Lungs: They remove or excrete CO2 as a waste product from the body.ii) Skin: Skin functions in excretion by sweating out waste products from the sweat glandsiii) Liver: The liver excretes cholesterol, steroid hormones, certain vitamins and drugs through the bile and also urea, ammonia, amino acids etc.2) Main Excretory Organi) Kidneys: Excretes waste products in the form of urineStructure & Working Of Kidney:External Structure:i) Renal Artery: The renal artery enters the kidney and brings oxygenated blood carrying toxic nitrogenous wastes into the kidneys.ii) Renal Vein: The renal vein drains away deoxygenated blood which is free of toxic substancesiii) Ureter: The ureter, a tube, runs from each kidney downwards into the lower part of the abdomen connecting each kidney to the urinary bladder. Its function is to transport the urine from the kidneys to the urinary bladder.\iv) Urinary Bladder: This is a large muscular storage sac that collects urine from both the kidneys through the ureters.v) Urethra: This is a short muscular tube that carries urine at intervals from the urinary bladder to the outside.Internal Structurei) Renal Cortex: This is the outer pale red colored layer.ii) Renal Medulla: This forms the inner dark red zoneiii) Renal Pelvis: This is a large funnel-shaped region behind the renal medulla.iv) Nephrons: These are structural and functional microscopic filtering units of the kidney. There are more than 1,250,000 nephrons in each kidney.Microscopic Structure of a Nephroni) Malpighian Corpuscle: This consists of two parts:a) Bowman's Capsule: This is a cup - shaped structure which is double walled in the hollow of which is a network of capillaries called the glomerulusb) Glomerulus: This is a knotted mass of blood capillaries formed by the afferent arteriole (incoming) and the efferent arteriole (outgoing).ii) Renal Tubule: This further consists ofa) Proximal Convoluted Tubule: This is the region behind the Bowman's capsule and consists of a coiled tube that descends to form the Henle's loop.b) Henle's loop: This is continuous with the proximal convoluted tubule and is U-shaped having a narrow descending limb and a thick ascending limbc) Distal Convoluted Tubule: This is another coiled and twisted tubule that continues from the ascending limb of loop of Henle found in the renal cortex.iii) Collecting Tubule: The distal convoluted tubule continues to form the collecting tubule.iv) Collecting Ducts: Several collecting tubules fuse to form large collecting ducts which pass downwards from the cortex to the medulla region.
Working Of The Kidney:• The nephron is the kidney’s functional unit.• In its first section renal corpuscles filtration occurs.• As fluid, small molecules and blood are filtered from glomerulus capillaries.• The filtered material called filtrate is captured in Bowman’s capsules.• Filtrate then enters the proximal convoluted tubule.• Reabsorption of important molecules and ions from the filtrate into the blood occurs here.• These include glucose, amino acids, vitamins, water, sodium, potassium, chloride and bicarbonates.• Filtrate then enters into Loop of Henle which consists of descending limb and ascending limb.• In descending limb only water is reabsorbed and in ascending limb only salt is reabsorbed.• In distal convoluted tubule secretion occurs. Ammonia, hydrogen ions, uric acid are secreted from blood vessels into the distal tubule. • As result concentrated fluid called urine is produced which enters into collecting.Composition Of Urine:The urine is composed of following substances:i) Water: 95%ii) Dissolved Substances: 5%a. Urea: 2%b. Uric Acid and other ammonium compound: 1%c. Organic and inorganic salts: 2%iii) Inorganic constituents
iv) Nitrogenous Constituentsv) Other Constituents.Functions Of Kidney:1) Excretory:• Excrete waste products especially nitrogenous substances• Eliminates drugs and toxic substances2) Synthetic• Synthesis ammonia and Hippuric acid3) Endocrine• Secretes Renin4) Regulatory• Maintains - pH balance- Sodium ion, potassium ion and electrolyte balance- Osmotic pressure in blood- Water balance, extra fluid volume- Blood pressure
Endocrine System:
Definition:The endocrine system is a control system of the body, which controls various functions of the human body through secretions known as hormones, secreted by the endocrine glands.
Endocrine Glands:Endocrine glands are secretary tissues (glands) which secrete hormones directly into the blood stream. They are also called ductless glands. The study of endocrine glands is called endocrinology.Important Endocrine Glands & Their Functions (secretions)Following are the important endocrine glands of the human body.i) Pituitary Glandii) Hypothalamusiii) Thymusiv) Pineal v) Thyroidvi) Parathyroid vii) Adrenalviii) Pancreasix) Testesx) OvariesPituitary Gland:The pituitary gland is a small bean-shaped reddish gray organ, located near the hypothalamus (forebrain). It produces at least nine hormones which perform following functions:Functions:- Responsible for normal skeletal growth, milk secretion in mammary glands.- Controls normal functioning of thyroid and adrenal glands- Stimulates the formation of the graffian follicles in the female ovary and development of spermatozoa in male.- Stimulate the contraction of the uterine muscles during the final stage of pregnancy- Control the amount of urine secreted by the kidney.HypothalamusThe hypothalamus is located immediately below the thalamus at the centre of the brain, and controls many automatic functions of the body.Function:The general functions of the hypothalamus are of extreme importance for the body, such as: - Pituitary gland regulation - Blood pressure regulation - Hunger and salt cravings - Feeding reflexes - Thirst - Body temperature regulation Thymus:The thymus gland, which is shaped like a pyramid, is a specialized organ of the human immune system. It is also one of the important glands in the human body. It is a pinkish gray colored organ that is situated in the upper thoracic region, under the sternum or the breast bone.Function:The thymus gland is very active, when the individual is a child. It plays a crucial role in developing and improving a child's immunity system. The main function of the thymus gland is to produce and process lymphocytes or T cells.Pineal Gland:
The pineal gland is a pine cone shaped gland of the endocrine system. A structure of the diencephalon of the brain, the pineal gland produces several important hormones including melatonin.Function:The pineal gland is involved in several functions of the body including:• Secretion of the Hormone Melatonin• Regulation of Endocrine Functions• Conversion of Nervous System Signals to Endocrine Signals• Causes Feeling of Sleepiness• Influences Sexual DevelopmentThyroid Gland:The thyroid gland is paired organ located in upper region of the neck in front of windpipe. It produces the hormone thyroxin (T4), Triiodothyronine (T3) and calcitonin.Functions:- Plays an important role in regulating the body's metabolism - The T4 and T3 hormones stimulate every tissue in the body to produce proteins and increase the amount of oxygen used by cells.- The calcitonin hormone works together with the parathyroid hormone to regulate calcium levels in the body.Parathyroid Gland:The parathyroid glands are embedded in the thyroid gland.Functions:- Controls the concentration of calcium (Ca ion) and phosphorus (phosphate) in the blood.- Stimulates the absorption of calcium and magnesium from the gut.- Increases tubular reabsorption of calcium, magnesium and hydrogen ions.Pancreas:The pancreas is located deep in the abdomen, sandwiched between the stomach and the spine. It produces two important hormones which are insulin and glucagon.Functions:- Insulin and glucagon are especially important for the maintenance of blood sugar, as insulin lowers the blood sugar and glucagon increases the blood sugar according to the body's needs.Adrenal Gland:The adrenal gland curve over the top of each kidney in abdomen. The important hormones secreted by adrenal gland are adrenaline, Aldosterone hormone, and cortisol.Function:- Adrenal glands are responsible for secreting hormones essential for carrying out some important metabolic processes. Besides, they also help the body in dealing with physical and mental stress. Ovaries:It is not only a reproductive organ which produces gametes but also make many steroidal hormones. The important ovary hormone is estrogen.Function:- Ovary hormones are responsible for female characteristics e.g. sound, body, bones, hair etc.Testes:It is not only a reproductive organ in males but also performs endocrine functions. Important hormone of testes is androgens.
Function:Testes hormones are responsible for the development of male characteristics in male e.g. sound, bones, hairy body etc.
Some Important Hormone Of Endocrine Glands.
i) Insulin: By Pancreasii) Thyroxin: By Thyroid Glandiii) Adrenalin: By Adrenal Glandiv) Oestrogen: Ovariesv) Testosterone: Testesvi) Cortisol: Adrenal Glandvii) Melatonin: Pineal Glandviii) Glucagon: Pancreasix) Aldosterone: Adrenal Glandx) Renin: Adrenal Gland
Exocrine Glands:
Exocrine glands are the glands which do not pour their secretions directly into blood (like endocrine glands) but into a duct. These are the glands with ducts and the effect of their secretions is not generalized on all tissues of the body but specialized.Example:i) Salivary Glandsii) Exocrine Pancreasiii) Lacrimal Glandiv) Bile Producing Cells of Liverv) Secretory Cells of Stomach and IntestineExocrine Pancreas:Pancreas secret pancreatic juice which contains a large number of digestive enzymes. Pancreatic juice goes to the intestine thorough a pancreatic duct and performs the function of digestion inside the intestine.Mammary Glands:Mammary glands are also exocrine glands which secret milk or colostrum. Milk is collected by a series of ducts and secreted outside the body.Salivary Glands:Salivary glands are present inside the jaw. These secret saliva which comes to the mouth (oral cavity) through salivary duct. Saliva is responsible for lubrication of food and early digestion of starch.Lacrimal Gland:Lacrimal is the gland which is present in the eye. Its secretion is the lachrymal secretion in the form of tears. Lachrymal secretion washes the eye and the lysozyme enzyme present in this secretion kill bacteria to protect eye.Bile Producing Cells Of Liver:The liver produces bile then it is stored in the gall bladder until need to digest fatty foods.Secretory Cells Of Stomach And Intestine:
Secretory cells of stomach secrete gastric juice which is poured into the stomach. Gastric juice contains enzyme like pepsin which digest proteins. Similarly secretory cells of intestine secrete intestinal juice which contains many digestive enzymes.Exocrine Glands And Their Secretions:
i) Lachrymal Gland: Tearsii) Sweat Gland: Sweatiii) Salivary Gland: Salivaiv) Mammary Glands: Milkv) Liver: Bilevi) Sebaceous Gland: Sebum
ii)Hormones:
Hormones are the chemical substances secreted by the endocrine glands. They carry electro-chemical messages to different parts of the body. Hormones are circulated in the body through blood. The function of endocrine system depends upon these hormones. These hormones work in the similar way as the nervous system works in the body. Insulin, glucagon, thyroxin and testosterone are few kinds of hormones. Hormones play an important role in a living organism. A small amount of hormones in the blood produces specific effects in the body. Several dozen hormones travel through the blood stream and influence different kinds of target cells, modifying their activity in a variety of ways.
iv) Antibody:
• Antibody is a protein produced by white blood cells that help to destroy bacteria.• Antibodies react with the antigens and inactivate or destroy them. • A large number of antibodies are produced in blood which are targeted against various types of antigens. • Antigens are foreign molecules, cells, bacteria, viruses or fungi which enter the body usually a disease causing microorganisms. • Antibodies are the integral part of the defence mechanism of human body. • They are also involved in immunity against disease.
vi) Haemophilia:
• It is a disease in which the person has prolonged blood clotting time resulting in excessive bleeding from injury.• It is due to the deficiency of vitamin K.• It is a semi lethal disease controlled by recessive gene.• It is less common in women than in men.
1. NATURE OF SCIENCE
Definition:
Science can be defined as study "Mainly concerned with the phenomenon of physical universe any or all of natural sciences or biological sciences." Or
Science as the "the field of study which attempts to describe and understand the nature of the universe in whole or part."
Science is the faculty to reason out the how and why of the things as they occur in the phenomenal world or the objective world...Basically science is the study of laws of nature and man has developed science by observing.Infact this subject has completely transformed our power over nature and the world outlook. Development of the modern technology is directly the outcome of the development of modern science. Without the scientific revolution the industrial revolution would not have been possible.
It has raised the human activity level by significant observations in the various fields of human existence. Whether it‘s the
Exploration of human health, industrial progress, agrarian developments and modern communication technologies, the benefits gained from this major subject are enormous Infact it would not be wrong to say that we are living in the age of science and is a dominant factor in our day to day existence.
2. CONTRIBUTIONS OF MUSLIM SCIENTISTS
Made lasting contributions in the fields of Mathematics, Astronomy, Music, Geography and History. He composed the oldest works on Arithmetic and on Algebra. The oldest Mathematic book composed by him is "Kitab ul jama wat tafriq" He is the first person who used zero and wrote"Hisab ul jabr Wal Muqabla" which is conceived to be an outstanding work on the subject which included analytical solutions of linear and quadratic equations.
In the field of Astronomy he compiled his own tables which formed the basis of later astronomical pursuits in both East and West. He also contributed in the field of geographical science by writing a noteworthy book KItab ul Surat al ard. In Arabic. His book ―kitab al Tarik" is also a memorable work regarding history.
AL BERUNI:
Born in Afghanistan Beruni made original important contributions to science. He is conceived to be the most prominent scientists of the Islamic world who wrote around 150 books on various significant subjects concerning human existence. These subjects include Mathematics, History, Archeology, Biology, Geology, chemistry, Religion etc.
He discussed the behavior of earth, moon, and planets in his book "Qanoon Almasudi" which is also considered as an outstanding astronomical encyclopedia. He also discovered seven different ways of finding the directions of north and south and discovered mathematical techniques to determine exactly the beginning of the seasons.
Another notable discovery he made was that the speed of light is faster than sound .His wide range of scientific knowledge is also revealed through his books" kitab al saidana" and "kitab al jawahar" dealing with medicine and the types of gems their gravity respectively.
He was a prolific writer whose works showed his versatility as a scientist.
AL RAZI:
The famous philosopher and a notable surgeon of the Muslim world, Zakriya Al Razi was born in Ray near modern Thehran Iran. His eagerness for knowledge lead him to the study of Alchemy and Chemistry, philosophy, logic, Mathematics and Physics. He was a pioneer in many areas of medicine and treatment of health sciences in general, and in particular he worked alot in the fields of pediatrics, obstetrics and ophthalmology.
Al razi was the first person to introduce the use of Alcohol for medical purposes and opium for the objective of giving anesthesia to his patients.
In the field of ophthalmology too Al razi gave an account of the operation for the extraction of the cataract and also the first cientist to discover the effect of the intensity of light on the eye. The modern studies confirm his understanding on the subject thus making him a great physician of all the times.
ABU ALI IBN E SINA:
Endowed with great powers of absorbing and retaining knowledge this Muslim scholar also made valuable contributions to the field of science. He is considered to be the founders of Medicine and also added his great efforts to the fields of Mathematics, Astronomy, Medicinal Chemistry, Philosophy, Palae ontology and Music.
His most famous book is "Al Qannun" which brings out the features of human physiology and medicine.
Sina is also considered as a father of the science of Geology on account of his invaluable book on mountains in which he discussed matters relating to earth's crust and gave scientific reasons for earthquakes. He is the author of 238 books which are fine instances of his thoughts regarding various subjects in diverse ways.
JABIR BIN HAYAN:
Introduced experimental research in chemical science which immensely added its rapid development and made him the Father of Chemistry. He devised methods for preparation of important chemicals like hydrochloric acid, nitric acid, and white lead.
Jabir's work also deal with the refinement of metals ,preparation of steel, dyeing of cloth and leather, use of magnese dioxide in glass making, distillation of vinegar to concentrate acetic acid.
Jabir also explained scientifically two principle functions of chemistry, i.e., calcinations, and reduction and registered a marked improvement in the methods of evaporation, sublimation, distillation and crystallization.
He wrote more than 100 books which are one of the most outstanding contributions in the field of science especially the chemical science.
ABDUL HASSAN IBN AL HAITHAM:
One of the most outstanding Mathematicians, Physiologists, and Opticians of Islam. He contributed to the realms of medicine and philosophy. He wrote more than 200 scientific works on diverse subjects.
Haitham examined the refraction of light rays through transparent objects including air and water. Infact he was the first scientist to elaborate two laws of reflection of light
He made a number of monumental discoveries in the field of optics, including one which locates retina as the seat of vision. His book on optics "Kitab Al Manazir" vividly shows his grip on the subject.
He constructed a pinhole camera and studied formation of images .Due to his noteworthy contributions he is regarded as one of the prolific Muslim scientists of all times.
OMAR AL KHAYAM:
He was an outstanding Mathematician and Astronomer. He was also known as a poet, philosopher and a physician. He travelled to the great centers of learning of the era i.e. Samrakund, Bukhara, and Ispahan.He classified many algebraic equations based on their complexity and recognized thirteen different forms of cubic equation. He also classified algebraic theories of parallel lines. On the invitation of Sultan Jalal-ud- Din, he introduced the Jilali calendar which has an error of one day in 3770 years. He also developed accurate methods for determination of gravity as a poet too, he is known for his Rubaiyat.He made great contributions in the development of mathematics and analytical geometry which benefitted Europe several years later.
NASIR UD DIN TUSI:
Al tusi was one of the greatest scientists, Mathematicians, Astronomers, Philosophers, Theologians and physicians of his time. He was a prolific writer and wrote many treatises on
varied subjects like Algebra, Arithmetic, Trignometry, Geometery, Logic, Met aphy sics, medicine, ethics and Theology.
He served as a minister of Halaku Khan and persuaded him to establish an observatory and library after the destruction of Baghdad. He worked at the observatory and prepared precise tables regarding the motion of the planets. These are also known as "Tables of Khan"
ZIA UD DIN IBN BAITAR:
Was a famous botanist and pharmacopeias of middle ages, Because of his intensive travels, he was able to discover many plant species. He wrote many books regarding his field of specialty and is always considered as a prominent scientist among his Muslim counterparts
3. IMPACT OF SCIENCE ON SOCIETY
Science is the organization of knowledge in such a way that it commands the hidden potential in nature. This hidden potential is surfaced out by the subject of science through the process of understanding. Science has proved to be of enormous beneficial nature .It has made lasting impact on regarding each and every field of human existence. Whether it is concerned with our day to day lives or whether it is related with the various modern developments which have resulted in elevating the living standards of the individuals.
The significant contributions which the study of this subject has made are enumerated below.
SCIENCE AND HUMAN ATTITUDE:
The various noteworthy scientific advances have helped the individuals in raising up of their self confidence .This subject has enabled the human beings to control and modify their needs and requriements.With greater understanding of the scientific phenomena human beings have now become more confident about the environmental issues as compared to the people in the past.Infact science has promoted and paved the way for the independent and logical thinking.
SCIENCE AND HUMAN HEALTH:
Before the development of modern medicinal factors, a large number of people used to lose their precious lives because of the unavailability of the sources and medicines for a proper health care. With the advancements of science now the human life expectancy rate has increased as the various modern developments in the field of health care has helped in warding off the dangerous diseases...
The revolutions in surgery and medicine the infectious diseases like small pox, malaria, typhoid etc. have been eradicated. Thus science has improved the health standards of the people.
SCIENCE AND TRAVEL:
People used to travel on foot before the inventions of automobiles, aeroplanes and steam engines. They also used animal carts and camels for the purpose of moving from one place to another. However, the modern scientific inventions have proved to be of great significance as it has added speed to the area of travel. The quick means of transportation have decreased the distances and are a source of saving time. In fact it would not be wrong to regard that these inventions have added much peace to the lives of the modern men.
SCIENCE AND COMMUNICATION:
Science has also played a significant part in the development of the modern communication technology. Earlier people were living in isolation because of the slow means of communication. Now the well developed, efficient media have made it possible to communicate with each other more rapidly and quickly. The impact of mass media is enormous. The use of computers and televisions has made the world a global village where an event in one part of the world leaves an influence on the other.
DEMERITS OF SCIENCE:
Every invention of science has got its own merits and demerits. The most serious invention that science has contributed to is the development of the weapons of mass destruction like the atom and nuclear bombs. The recent wars have greatly showed that how much destruction can be brought about with the use of these lethal weapons. In fact these modern inventions of science have resulted in the elevation of the anxiety and unrest in the modern societies.
Another notable demerit which the study of this subject has lead to the rise in the environmental deterioration. Day by day the pollution factor is increasing which has proved to be very toxic and harmful for the human health. Not only the human health it is also proving fatal for the animals as well as the existing plants.
The rapid developments of science and industrialization have also divided the world. The developed and the undeveloped. This division has lead to a widening gap between the status and the living standards of people. There is economic disparity which has also given rise to class distinction.
1.The Earth bulges out at equator. Why?
Ans: This is due to the shape of the earth. The earth is not a true sphere but it is an ellipsoid. The equatorial diameter of the earth is 12756.27 kms. While its polar diameter is 12713.505 km. the difference between its equatorial and polar diameter is about 43 kilometers. The rotation of the earth on its axis produces a centrifugal force which increases its equatorial diameter. That is why earth bulges at the equator.
2.The Sun appears red at sunset and sunrise. Why?
Ans: The sun appears red at the time of sunset and sunrise due to the scattering of light by small particles of dust or smoke near the surface of the earth. The light travels relatively without hindrance that is why the sun appears red at the time of sunset and sunrise.
3.The ozone layer in the atmosphere is necessary for our survival. Why?
Ans: ozone layer in the atmosphere is very necessary for plant and animal survival because it is the absorber of ultraviolet rays which are very dangerous for animal health. Ultraviolet rays cause cancer of skin, spotting of plants etc. that is why the ozone layer is necessary and essential for animal as well as plant survival.
4.The sky from moon appears black. Why?
Ans: as the moon has no atmosphere, so the sky looks completely black when viewed from the moon.
5) Roads are bent inwards on curves. Why?
Ans: The roads are bent inwards on the curves and at the turns because the bents avoid falling outside and prevent the accidents. OR When an object turns in a circle it is influenced by a centrifugal force which pushes it away from the centre of the circle. When vehicles turn on a road they fall outside under the influence of centrifugal force. In this way there is danger of falling or slipping out of road at a turn. Roads are made in a way that these bent inward at the turns to avoid falling outside and to prevent accidents.
6) Australian continent has winter season when we have summer season in Pakistan.
Ans: the earth on its axis is not at a vertical angle to its orbit. It is inclined at an angle of about. In this way when the northern hemisphere of the earth is inclined to the sun and getting direct sun rays, southern hemisphere is inclined away from the sun and getting less direct rays. Thus the northern hemisphere has summer season and southern hemisphere has winter season. Pakistan is in the northern hemisphere while Australia is in the southern hemisphere. So when there is winter in Australia there is summer season in Pakistan.
7.Meat takes longer to cook on mountains.
Ans: The meat takes longer time to cook on the mountains because the atmospheric pressure decreases with attitude and the boiling point of a liquid is directly proportional to the atmospheric pressure.
8.Water remains cool in earthen pitcher.
Ans: This occurs due to the process of evaporation. Water gets cooled on evaporation. As the earthenware pitcher is concerned, they have small pores. Water tends to come out of pores and evaporates which results in cooling effect on the earthenware and water. While in the metal pots
there are no pores and evaporation does not take place. Besides metal has tendency to absorb heat that why water does not get cooled in a metal pot.
9.Ice and salt mixture is used as a freezing agent by manual ice-cream makers.
Ans: In manual ice-cream making a mixture of salt and ice is always used because salt has capacity to reduce the temperature of ice by decreasing its freezing point. That’s why ice and salt mixture is used as freezing agent in manual ice cream making.
10.It is not advisable to sleep under trees during the night.
Ans: During night the plants release carbon dioxide (CO2) which is a poisonous gas and injurious to health. That is why it is not advisable to sleep under trees during night.
11.Why the green house operators paint their glass roofs white in summer?
Ans: White colour is the reflector of light and it absorbs less heat as compared to other colours. As in summer there is already very hot season and heat is not required to that level. That is why the green-house operators paint glass roofs white in summer season.
12) Water boils quicker on mountains.
Ans: On Mountains the pressure of the air is low due to height, as the air pressure decreases with altitude. In this way, water boils quicker on mountains at temperature less than 100 degree centigrade, which is the boiling point of water at ground level.
13.Rainbow is produced in the sky after rainfall and sunlight.
Ans: After rain, many droplet of water travel in the atmosphere. When sun rays fall on these droplets, dispersion of water occurs and droplets act as prism and produce a spectrum of seven colours. That’s why a rainbow is seen in the sky after rain.
14.Milk is considered as an ideal food.
Ans: Milk is considered as an ideal food due to following reasons: a) It contains all constitute of balanced diet. b) Milk contains fat. c) Milk has high nutritional value because it contains proteins as well as minerals.
15.Lunar eclipse last much longer than solar eclipse.
Ans: Lunar eclipse last longer than the solar eclipse because the length of the earth’s umbral shadow cone is more than three times the average distance between the moon and the earth, so the shadow is relatively wide at the point where the moon crosses it.
16.Goitre is common in hilly areas.
Ans: Goitre is common in hilly areas because there is deficiency of Iodine in the water.
17) Detergents are better cleaning agents.
Ans: A detergent consists of hydrophilic and hydrophobic ends. In case of dirt the detergent pushes the dirt off the wet surface of the fabric. The washing machine provides the agitation.
18) Decomposers are important for life.
Ans: Decomposers break down animal waste and dead organisms in order to get energy and release free nutrients back into the ecosystem.
OR
Decomposers break down organics into nutrients, which can be used by living organisms to create new life.
19) Places near sea are cooler in summer.
Ans: Sea water keeps the temperature moderate. In the summer season the places located near sea are cooler due to the lower temperature of water.
20) Colour blindness is more common in men than women.
Ans: Women have the sex chromosomes XX, while men have the chromosomes XY. The gene for normal colour vision is found on the X-chromosome. If a woman has one X-chromosome with the gene and one without it, she will not be colour blind. On the other hand, a man with an X-chromosome that is missing the gene has no 'backup'. He will definitely be colour blind. Colour blind women have both X-chromosomes missing the colour vision gene. This is less probable mathematically than having just one X-chromosome missing the gene.
21) Light colours absorb less heat therefore these are not heated as much as the black colour.
Ans: Dark colours do not exactly absorb more heat, but they do convert a higher percentage of light into heat. In the sun with a dark coloured shirt it gets hot, where a lighter coloured shirt would not get nearly as hot. This is due to the amount of light being absorbed by the colour. The lighter the colour the smaller is the range of visible light being absorbed and converted into heat. White objects reflect all visible light, where black objects absorb all visible light.
22) Rain water is more fertile than water from tube well.
Ans: Rain water is more fertile because it contains many salts and nitrogen dissolved from the atmosphere.
23) The manhole covers are generally round.
Ans: Manholes, which interconnect underground sewerage pipes, and serve as a point of entry for cleaning the pipes, are located at every major sewer pipe junction, and are capped with round manhole covers. The reason for the circular construction of these covers is, quite simply, that covers of any other shape would fall through the manholes by virtue of their varying diameters. Circular manhole covers do not vary in width, or in diameter, as is the case with these other shapes, thus remaining in place despite the street traffic running roughshod over them.
24) Clothes of a moving dancer bulge.
Ans: The clothes of a moving dancer bulge outside due to the centrifugal force which tends to move away from the centre.
25) People are advised not to stand near fast moving train.
Ans: One should not stand beside a fast moving train because of the strong pressure of air which carries along. A man can fall in this pressure.
26) The image of a tree is inverted on the bank of a lake.
Ans: The water of lake acts as a mirror. According to the laws of light, mirror forms inverted images.
27) Polar star is always seen in the north.
Ans: It is because the Polar Star (North Star) is closest to the location of the celestial North Pole.
28) We never see birds urinating.
Ans: The birds do not have a urinary system like other living beings which possess urinary excretory organs. In the birds the urine is excreted from body without special organs.
29) Pasteurized milk has more nourishment than the ordinary boiled milk.
Ans: Pasteurized milk is obtained by heating milk at a temperature of 60 degree Celsius for 30 minutes. In this way the TB bacteria are killed without damaging the milk protein. Thus pasteurized milk has more nourishment than ordinary boiled milk.
30) Bees die when they sting human being.
Ans: Their stingers are actually ovipositors, tubular structures extending from the abdomen that sometimes contain eggs. When the barbed stinger is left inside the victim, the honeybee mortally tears her abdomen in the process. They leave their stingers in the wound with a tiny venom sac attached. Fortunately, only about one out of a hundred people are allergic to bee sting, but allergic reactions can be very serious.
31) Cloudy nights are usually warmer than the clear ones.
Ans: The clouds serve as a barrier and prevent the loss of heat. Thus the warm temperature is maintained.
32) Why do some people snore?
Ans: Some people snore during their sleep because the breathing action produces sound. This is so because the pharynx or the windpipe offers resistance to the air taken in or expelled.
33) Why do we sometimes sleep walk?
Ans: Sleep walk is a sort of disorder of sleep in which a person starts walking during his sleep. The sleeper walks and performs complex activities automatically without regaining consciousness.
34) Climbers bend forward while climbing mountain.
Ans: While climbing a mountain, a climber bends his body forward in order to keep the centre of gravity of his body within two thirds portion. According to this principle the Pisa Tower is not falling.
35) Why climbers get their food by climbing on other trees?
Ans: The climbers are mostly parasites and they cannot manufacture their food. Therefore, they climb on other trees and get food from them.
36) Mars is called red planet.
Ans: Mars is called the red planet because its colour is red due to the desert like surface.
37) Vitamin D is the essential component of the body.
Ans: Vitamin D is necessary for body because it is essential for bone formation and retention of calcium in the human body. Vitamin D also protects the teeth.
38) The weight of the object is less at the equator than at the poles.
Ans: The weight of an object is the product of mass and force of gravity. The equatorial diameter is more than the polar diameter. Thus, the force of gravity is more at the poles and the weight is more there.
39) The dogs pant, the birds open their mouth and the elephants move rapidly their ears.
Ans: All of them do not sweat; they use the above mentioned mechanisms to cool themselves.
40) A geostationary satellite appears standstill to a viewer on the equator of earth.
Ans: Because the distance remains the same.
41) Why do the stars twinkle?
Ans: The light from the stars travels through different layers of space of varying densities. Therefore, the light rays deviate from their original path. Further, these layers are not stationary but keep on moving. This leads to the twinkling of stars.
42) On what days do we have equal days and nights all over the world? And why?
Ans: On 23 September and 21 March we have equal days and nights all over the world. This is so because on these days, the rays of the sun fall vertically on the equator at noon. Both the poles receive equal rays of the sun. As a result, exactly one-half of each hemisphere receives the sun’s rays. This makes day and night equal.
43) Every fourth year has 366 days. Explain.
Ans: One revolution of the earth around the sun takes 356 days and 6 hours. But we consider a year as consisting of only 365 days and ignore 6 hours. In four years the difference becomes as much as 24 hours or one day. Hence, to every fourth year we add one day. That year of 366 days is known as leap year.
44) Why are igneous rocks called primary or parent rocks?
Ans: Igneous rocks are formed when the molten material from volcanoes gets solidified. This material is liquid, hot and sticky which moves towards the surface through cracks and joints. All other rocks derived from these rocks. Hence, they are called primary or parent rocks.
45) Why are the areas lying between the Arctic Circle and the North Pole in the Northern?
Hemisphere and the Antarctic Circle and the South Pole in the Southern Hemisphere very cold?
Ans: These areas are very cold because the sun does not rise much above the horizon. Therefore, its rays are always very slanting which emit minimum heat. These areas being very cold are called Frigid Zones.
46) Why are the three hot regions of the world-equatorial forests, savannah lands and hot deserts-not found in Europe?
Ans: The three hot regions of the world-equatorial forests, savannah lands and hot deserts-are not found in Europe because Europe is the only inhabited continent situated entirely outside the tropics.
47) Why is the lowest layer of the atmosphere in contact with the earth’s surface, the warmest?
Ans: The lowest layer of the atmosphere in contact with the earth’s surface is the warmest because the atmosphere is heated mainly from the below.
48) Why does the temperature above the ocean and land masses vary even on the same latitude?
Ans: Temperature above the oceans and land masses varies even on the same latitude because of the differential heating of land and water, i.e., land mass is heated and cooled more rapidly and to a greater degree than water.
49) Why are marine animals able to live at great depths than marine plants?
Ans: As marine animals do not depend upon sunlight for their survival, they are able to live at great depths where there is permanent darkness.
50) Why do trees of coniferous forests possess needle-like leaves?
Ans: The needle-like leaves limit transpiration and thus enable conifers to grow in the drier areas.
51) Why do equatorial forests appear evergreen?
Ans: In equatorial forests trees often shed a few leaves or shed their leaves seasonally, but most of the trees retain their leaves for most of the time so that the forests appear evergreen.
52) Why is petroleum often called black gold?
Ans: Petroleum is often called black gold because of its great demand in the modern industry and for domestic use. It provides fuel for heat and lighting, lubricant for machinery and raw material for a number of industries.
53) Why are the kangaroos called marsupials?
Ans: Marsupial means broad-pouch. Since kangaroos have a pouch-like fold of skin near the stomach in which they carry their young ones, they are called marsupials.
54) Why is platypus considered a strange animal?
Ans: Platypus is a strange animal because it is an animal-bird that survives under water, walks on the ground and digs tunnel under the ground. It is a four-legged animal that lays eggs like a bird. It is found in Australia.
55) Why is a person in moving vehicle thrown forward when the vehicle stops suddenly?
Ans: A person in a moving vehicle is in a state of motion. When the vehicle suddenly stops his body tends to remain in a state of motion due to inertia and he is thrown forward.
56) Earth is continuously pulling moon towards its centre. Why does not the moon fall on to the earth?
Ans: it is so because the gravitational attraction of the earth provides the necessary centripetal force to the moon for its orbital motion around the earth due to which the moon is revolving around the earth.
57) Which of the two-glass or rubber is more elastic and why?
Ans: Glass is more elastic than rubber because for a given applied force per unit area, the strain produced in glass is much more than that produced in rubber.
58) Animal like camel can easily walk in the desert sand while other animals like donkeys, dogs and horses cannot. Explain.
Ans: The camel has very broad and large feet. As a result of the large surface area in contact with the ground, it exerts less pressure on the sand and sinks only slightly in it. Other animals have smaller feet which exert more pressure on the sand. As a result, they sink more in the sand and cannot walk easily in desert.
59) Why does a small quantity of liquid assume spherical form?
Ans: A small quantity of liquid assumes a spherical form due to surface tension which tends to reduce the surface area. A given mass will acquire minimum surface area if it assumes a spherical shape.
60) Why does an iron needle float on clean water but sink when some detergent is added to this water?
Ans: Due to surface tension, the free surface of liquid at rest behaves like a stretched membrane. When an iron needle floats on the surface of clean water, its weight is supported by the stretched membrane. When some detergent is added to this water, its surface tension decreases. As a result of it, the stretched membrane on the surface of water is weakened and is not able to support the weight of needle. Hence the needle sinks in such water.
61) Why is cooking quicker in a pressure cooker?
Ans: The boiling point of water depends upon the pressure on its surface. Steam produced inside the cooker builds up pressure thereby raising the boiling point of water, which results in quick cooking.
62) Why does steam cause more severe burns than boiling water?
Ans: The amount of heat (latent heat) possessed by steam is much greater than the amount of heat possessed by water at the same temperature. Therefore, steam causes more severe burns than boiling water.
63) Why does ice not melt readily when salt is sprinkled over it?
Ans: When salt is sprinkled over ice, some of it dissolves. As dissolution of the salt is accompanied by absorption oh heat. The temperature of the system falls below 0 degree Celsius. Hence, ice does not melt readily.
64) It is difficult for firemen to hold a hose, which ejects large amount of water at a high velocity. Why?
Ans: the water which comes out of the fireman’s hose carries large momentum as its velocity is very high. The equal and opposite reaction force pushes the fireman backwards with a great speed satisfying the law of conservation of momentum. As a result, it is difficult for the fireman to hold the hose.
65) In the outer space astronauts talk to each other through radios. Why?
Ans: sound waves need a material medium for its propagation. There is no air in space and hence, sound waves cannot travel. However, radio waves can travel through space. The astronauts can see each other because light, like radio waves, can travel through vacuum.
66) Sonar scanners are used by doctors. Explain.
Ans: sonar scanners send out ultrasonic waves, which are reflected by body tissue and organs. From the pattern of reflections, a computer can build up an image of the internal structure which is vital for diagnosis.
67) Why the flash of lightning is seen before the sound of thunder is heard?
Ans: the velocity of light is much greater than that of the sound. Therefore, flash of lightning is seen before the sound of thunder is heard.
68) Bats have poor eyesight but are able to home their prey with great accuracy. Also, dolphins can avoid fishing nets and can detect fish at night. Explain
Ans: Bats emit high frequency (1, 20,000 Hz) sound waves and listen with their sensitive ears for any echoes. From the time taken to hear the echo and from the nature of sound received. Bats are able to estimate the distance and the type of surroundings. This process is known as echolocation. Same process is used by the dolphins.
69) When low flying aircraft passes overhead, we sometimes notice a slight disturbance on our TV screen. Why is it so?
Ans: a low flying aircraft reflects TV signal. Due to the interference between the direct signal and the reflected signal, there is disturbance on the TV screen.
70) In automobiles, why are convex mirrors used to see the traffic from behind?
Ans: Convex mirrors are used in automobiles because they form erect and diminished images of the object. Thus, it helps the drivers to get a wider field of view of the traffic coming from behind.
71) Why is mirage formes in the deserts?
Ans: A mirage is formed owing to total internal reflection. To the observer at a distance, the reflected image of the object appears behind the reflecting surface, as if the object were in front of it, but actually it is just an illusion.
72) What will be the colour of grass in blue light?
Ans: Grass will appear blackish in colour in blue light because it has the property of absorbing all other colours except its own colour. The blue rays falling on grass will be absorbed by it, and it will appear dark coloured.
73) A bird perches on a bare high power line and nothing happens to it. A man standing on
the ground touches the same line and gets a fatal shock. Why?
Ans: When bird perches on a live high power line, no current passes through the body of bird because there is no potential difference between live wire and the body of bird as the potential of bird’s body is the same as that of wire. When a man standing on the ground touches the same wire then due to a large potential difference between his hands and feet, a large current flows through his body to the earth.
74) During lightning it is safest to be inside a car rather than under a tree or in the open. Give reason.
Ans: When a person is in the open or under the tree, the lightning passes through his body to the earth. On the other hand, for a person inside a car, the car provider shielding and the electric field inside the car is zero, thus lightning does not affect the person inside it. The lightning actually passes through the metallic body of the car to the earth without affecting the person sitting inside it.
75) Why is earthing desirable for electric appliances?
Ans: Earthing helps the current move into the earth in the event of short-circuit, without giving a shock to the user.
76) Why does a perspiring man feel relief when air flows by his side?
Ans: The air flowing by the side of a perspiring man quickens the pace of evaporation of perspiration from the body of that person, and the resultant loss of heat from his body causes the cooling sensation which provides relief to him.
77) Why is magnet always made of soft iron?
Ans: Magnet is always made of soft iron because ‘magnetization’ and ‘demagnetization’ both are possible in soft iron.
78) Why are telephone wires between two poles kept loose?
Ans: Telephone wires are kept loose between two poles so that they are protected from being broken due to expansion and contraction caused by the change of temperature in summers and winters.
79) X-rays penetrate through the flesh but not through bones. Why?
Ans: The penetrating power of X-rays depends upon the potential difference between the cathode and the anode of X-ray tube. The X-rays produced can penetrate through light element like flesh of human body but they are unable to penetrate through heavier elements like bones.
80) What is a black hole? Why is it called so?
Ans: A black hole is a super dense planetary material formed due to the death of a star of mass more than five solar masses. It is called black hole because any particle or photon approaching its surface is just swallowed by it. It appears black, as radiation is neither emitted nor reflected by it.
81) Why do water pipes burst in severe cold winters?
Ans: Water freezes in pipes during winters, when the temperature goes below 0 degree Celsius (i.e., freezing point of water). It expands and in the process exerts pressure on the water pipes, thereby sometimes bursting them.
82) Most aircrafts and ships have their front shape pointed. Why?
Ans: The shape of many objects, viz. aeroplanes, rockets, ships, etc. moving through air or water, is designed in such a way that friction can be reduced between the objects and air/water. Such type of body is known as streamlined and the process is known as streamlining.
83) An athlete runs some distance before taking jump, why?
Ans: An athlete runs a certain distance before actually jumping in order to increase his speed, and thereby, his inertia of motion. This increased inertia of motion enables him to jump a longer distance.
84) It is difficult to drown in the Dead Sea. Why?
Ans: The water of Dead Sea has a salt content of 27%. Therefore, its density is much greater than that of ordinary sea water and it also offers a greater upthrust. Hence, the body weighs less than an equal volume of Dead Sea water and is thus, able to float.
85) Why aquatic animals have soft skeleton unlike those of the terrestrial animals?
Ans: The density of animals and fish living in water is almost the same as the density of water. Therefore, their weight is almost completely balanced by buoyancy. That is why they do not need massive skeleton like those of terrestrial animals.
86) Why does a swimming pool appear less deep than it really is?
Ans: When rays of light start from the bottom of a pool and travel from water to air, they are refracted away from the normal because they travel from a denser medium to a rarer medium. As a result, a virtual image of bottom is formed above the bottom. Hence, a swimming pool appears less deep than it really is.
87) Why is electrical wiring in parallel better?
Ans: electrical wiring in parallel is better because all the lines will have the same potential difference and if one line gets fused the other lines remain unaffected.
88) It is easier to swim in sea water than in river water. Explain.
Ans: The density of sea water is more than that of the river water. Therefore, the weight of sea water displaced by the swimmer is more. Thus, buoyant force of up thrust on the swimmer increases, making it easier to swim in sea water.
89) A cold compress is applied on the forehead of a person suffering from high fever. Why?
Ans: Evaporation causes cooling. As the water evaporates, it absorbs heat from the forehead and helps in reducing the temperature.
90) A man with a load his head jumps from a high building. What will be the load experienced by him.
Ans: Zero, because the acceleration of his fall is equal to the acceleration due to gravity of the earth.
91) Why is spring made of steel and not copper?
Ans: The elasticity of steel is greater than that of copper.
92) Why is it easier to spray water to which soap is added?
Ans: Addition of soap decreases the surface tension of water. The energy for spray is directly proportional to surface tension.
93) A piece of chalk when immersed in water, emits bubbles. Why?
Ans: Chalk consists of pores forming capillaries. When it is immersed in water, the water begins to rise in the capillaries and air present there is expelled in the form of bubbles.
94) Why does a liquid remain hot or cold for a long time inside a thermo flask?
Ans: Because of the presence of air, which is poor conductor of heat, in between the double glass walls of a thermos flask?
95) Why is the boiling point of sea water more than that of pure water?
Ans: Sea water contains salts and other impurities with different points which jointly rise its boiling point.
96) Why is it recommended to add salt in water while boiling grams?
Ans: By addition of salt the boiling point of water gets which helps in cooking.
97) Why is soft iron used as an electromagnet?
Ans: Because it remains magnetic only till the current passes through the coil and loses its magnetism when the current is switched off (principle of electric bells)
98) Why does ink leak out of a partially filled pen when taken to a high altitude?
Ans: As we go up the pressure and the density of air go on decreasing. Partially filled pen leaks when taken to a higher altitude because the pressure of air acting on the ink inside the tube of the pen is greater than the pressure of air outside.
99) Why does some liquids burn while others do not?
Ans: A liquid burns if its molecules can combine with oxygen of the air with the production of heat. Hence, oil burns but water does not.
100) Oil and water do not mix. Why?
Ans: i) Molecules of oil are not bigger than that of water and therefore do not mix easily. ii) Molecules of water are polar, i.e. they have opposite charges at two ends whereas oil molecules do not; as a consequence they tend to stay away from water molecule.
Scientific studies of various fields
шаблоны YooThemeшаблоны Недвижимости joomla
sc
acarology-- study of mites
accidence-- grammar book; science of inflections in grammar
aceology-- therapeutics
acology -- study of medical remedies
acoustics -- science of sound
adenology -- study of glands
aedoeology -- science of generative organs
aerobiology -- study of airborne organisms
aerodonetics-- science or study of gliding
aerodynamics -- dynamics of gases; science of movement in a flow of air or gas
bacteriology -- study of bacteria
balneology -- the science of the therapeutic use of baths
barodynamics-- science of the support and mechanics of bridges
barology-- study of gravitation
batology-- the study of brambles
bibliology-- study of books
bibliotics-- study of documents to determine authenticity
bioecology-- study of interaction of life in the environment
biology -- study of life
biometrics-- study of biological measurement
bionomics-- study of organisms interacting in their environments
botany-- study of plants
bromatology -- study of food
brontology -- scientific study of thunder
campanology-- the art of bell ringing
carcinology-- study of crabs and other crustaceans
cardiology-- study of the heart
caricology-- study of sedges
carpology -- study of fruit
cartography -- the science of making maps and globes
cartophily-- the hobby of collecting cigarette cards
castrametation -- the art of designing a camp
catacoustics--science of echoes or reflected sounds
catalactics-- science of commercial exchange
catechectics -- the art of teaching by question and answer
cetology -- study of whales and dolphins
chalcography-- the art of engraving on copper or brass
chalcotriptics-- art of taking rubbings from ornamental brasses
chaology -- the study of chaos or chaos theory
characterology -- study of development of character
chemistry-- study of properties of substances
chirocosmetics-- beautifying the hands; art of manicure
diabology-- study of devils
diagraphics-- art of making diagrams or drawings
dialectology -- study of dialects
dioptrics -- study of light refraction
diplomatics -- science of deciphering ancient writings and texts
diplomatology-- study of diplomats
docimology-- the art of assaying
dosiology-- the study of doses
dramaturgy -- art of producing and staging dramatic works
Egyptology-- study of ancient Egypt
ekistics-- study of human settlement
electrochemistry-- study of relations between electricity and chemicals
electrology -- study of electricity
electrostatics-- study of static electricity
embryology-- study of embryos
emetology -- study of vomiting
emmenology -- the study of menstruation
endemiology-- study of local diseases
endocrinology-- study of glands
enigmatology-- study of enigmas
entomology-- study of insects
entozoology-- study of parasites that live inside larger organisms
enzymology-- study of enzymes
ephebiatrics-- branch of medicine dealing with adolescence
epidemiology-- study of diseases; epidemics
fluviology -- study of watercourses
folkloristics-- study of folklore and fables
futurology-- study of future
garbology-- study of garbage
gastroenterology -- study of stomach; intestines
gastronomy-- study of fine dining
gemmology-- study of gems and jewels
genealogy-- study of descent of families
genesiology-- study of reproduction and heredity
genethlialogy-- the art of casting horoscopes
geochemistry-- study of chemistry of the earth's crust
geochronology--- study of measuring geological time
geogeny-- science of the formation of the earth's crust
geogony-- study of formation of the earth
geography-- study of surface of the earth and its inhabitants
geology -- study of earth's crust
geomorphogeny-- study of the origins of land forms
geoponics-- study of Agriculture
hydrography-- study of investigating bodies of water
hydrokinetics-- study of motion of fluids
hydrology-- study of water resources
hydrometeorology-- study of atmospheric moisture
hydropathy -- study of treating diseases with water
hyetology-- science of rainfall
hygiastics -- science of health and hygiene
hygienics-- study of sanitation; health
hygiology-- hygienics; study of cleanliness
hygrology-- study of humidity
hygrometry -- science of humidity
hymnography-- study of writing hymns
hymnology -- study of hymns
hypnology-- study of sleep; study of hypnosis
hypsography-- science of measuring heights
iamatology -- study of remedies
iatrology-- treatise or text on medical topics; study of medicine
iatromathematics-- archaic practice of medicine in conjunction with astrology
ichnography-- art of drawing ground plans; a ground plan
ichnology-- science of fossilized footprints
ichthyology-- study of Fish
iconography-- study of drawing symbols
iconology-- study of icons; symbols
ideogeny-- study of origins of ideas
ideology -- science of ideas; system of ideas used to justify behaviour
idiomology-- study of idiom, jargon or dialect
idiopsychology-- psychology of one's own mind
immunogenetics-- study of genetic characteristics of immunity
immunology-- study of immunity
immunopathology-- study of immunity to disease
insectology -- study of insects
irenology -- the study of peace
koniology -- study of atmospheric pollutants and dust
ktenology -- science of putting people to death
kymatology -- study of wave motion
labeorphily-- collection and study of beer bottle labels
larithmics-- study of population statistics
laryngology -- study of larynx
lepidopterology -- study of butterflies and moths
leprology-- study of leprosy
lexicology -- study of words and their meanings
lexigraphy-- art of definition of words
lichenology -- study of lichens
limacology-- study of slugs
limnobiology-- study of freshwater ecosystems
limnology -- study of bodies of fresh water
linguistics -- study of language
lithology-- malariology study of malaria
mammalogy-- study of mammals
manège-- the art of horsemanship
Mariology-- study of the Virgin Mary
martyrology-- study of martyrs
mastology-- study of mammals
mathematics-- study of magnitude, number, and forms
mazology-- mammalogy; study of mammals
mechanics -- study of action of force on bodies
meconology-- study of or treatise concerning opium
melittology -- study of bees
mereology-- study of part-whole relationships
mesology -- ecology
metallogeny-- study of the origin and distribution of metal deposits
metallography-- study of the structure and constitution of metals
metallurgy-- study of alloying and treating metals
nidology -- study of nests
nomology-- the science of the laws; especially of the mind
noology-- science of the intellect
nosology -- study of diseases
nostology-- study of senility
notaphily-- collecting of bank-notes and cheques
numerology -- study of numbers
numismatics-- study of coins
nymphology-- study of nymphs
obstetrics-- study of midwifery
oceanography-- study of oceans
oceanology -- study of oceans
odology -- science of the hypothetical mystical force of od
odontology-- study of teeth
oenology-- study of wines
oikology -- science of housekeeping
olfactology-- study of the sense of smell
ombrology -- study of rain
oncology -- study of tumours
oneirology -- study of dreams
orthography-- study of spelling
orthopterology-- study of cockroaches
oryctology -- mineralogy or paleontology
osmics-- scientific study of smells
osmology-- study of smells and olfactory processes
osphresiology-- study of the sense of smell
osteology -- study of bones
otology -- study of the ear
otorhinolaryngology-- study of ear, nose and throat
paedology-- study of children
paedotrophy-- art of rearing children
paidonosology-- study of children's diseases; pediatrics
palaeoanthropology-- study of early humans
palaeobiology -- study of fossil plants and animals
palaeoclimatology-- study of ancient climates
palaeolimnology-- study of ancient Fish
palaeolimnology-- study of ancient lakes
palaeontology-- study of fossils
philately-- study of postage stamps
philematology -- the act or study of kissing
phillumeny-- collecting of matchbox labels
philology -- study of ancient texts; historical linguistics
philosophy-- science of knowledge or wisdom
phoniatrics -- study and correction of speech defects
phonology -- study of speech sounds
psychology-- study of mind
psychopathology-- study of mental illness
psychophysics-- study of link between mental and physical processes
pteridology -- study of ferns
pterylology -- study of distribution of feathers on birds
pyretology -- study of fevers
pyrgology -- study of towers
pyroballogy-- study of artillery
pyrography-- study of woodburning
quinology -- study of quinine
raciology-- study of racial differences
radiology-- study of X-rays and their medical applications
reflexology-- study of reflexes
rhabdology -- knowledge or learning concerning divining rods
rhabdology -- art of calculating using numbering rods
rheology -- science of the deformation or flow of matter
rheumatology-- study of rheumatism
rhinology-- study of the nose
rhochrematics-- science of inventory management and the movement of products
runology -- study of runes
sarcology-- study of fleshy parts of the body
satanology -- study of the devil
scatology-- study of excrement or obscene literature
schematonics-- art of using gesture to express tones
sciagraphy-- art of shading
scripophily -- collection of bond and share certificates
sedimentology -- study of sediment
seismology -- study of earthquakes
selenodesy-- study of the shape and features of the moon
selenology-- study of the moon
semantics -- study of meaning
semantology-- science of meanings of words
semasiology-- study of meaning; semantics
topology-- study of places and their natural features
toponymics-- study of place-names
toreutics -- study of artistic work in metal
toxicology -- study of poisons
toxophily -- love of archery; archery; study of archery
traumatology-- study of wounds and their effects
tribology -- study of friction and wear between surfaces
trichology-- study of hair and its disorders
trophology-- study of nutrition
tsiganology-- study of gypsies
turnery-- art of turning in a lathe
typhlology-- study of blindness and the blind
typography-- art of printing or using type
typology-- study of types of things
ufology-- study of alien spacecrafturanography-- descriptive astronomy and mappinguranology-- study of the heavens; astronomyurbanology-- study of citiesurenology-- study of rust moldsurology -- study of urine; urinary tractvenereology-- study of venereal disease
vermeology-- study of wormsvexillology-- study of flagsvictimology-- study of victimsvinology -- scientific study of vines and winemakingvirology-- study of virusesvitrics-- glassy materials; glassware; study of glasswarevolcanology -- study of volcanoesvulcanology-- study of volcanoesxylography-- art of engraving on woodxylology -- study of woodzenography-- study of the planet Jupiterzoiatrics-- veterinary surgeryzooarchaeology-- study of animal remains of archaeological siteszoochemistry-- chemistry of animalszoogeography-- study of geographic distribution of animalszoogeology -- study of fossil animal remainszoology-- study of animalszoonomy-- animal physiologyzoonosology-- study of animal diseaseszoopathology-- study of animal diseaseszoophysics-- physics of animal bodieszoophysiology -- study of physiology of animalszoophytology-- study of plant-like animalszoosemiotics-- study of animal communicationzootaxy-- science of classifying animalszootechnics-- science of breeding animalszygology -- science of joining and fasteningzymology -- science of fermentationzymurgy-- branch of chemistry dealing with brewing and distilling
MCQ Everyday Science
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Every Day science Sr. No. Questions Answers
1. When a gas turns into a liquid, the process is called(a) condensation(b) evaporation(c) deposition(d) sublimation
Answer: (a)
2. Which of the following elements is a metal?(a) S(b) Se(c) I(d) Ga
Answer: (d)
3. Oranges are rich source of(a) Carbohydrates(b) Fats(c) Proteins(d) Vitamins
Answer: (d)
4. Most plant and animal cells are similar in some respects since they both have in common(a) Cytoplasm and cellulose(b) Cytoplasm and contractile vacuole(c) Cytoplasm and nucleus(d) Membrane and cell wall
Answer: (c)
5. Lamarck's theory of inheritance of acquired characters was challenged by(a) August Weismann(b) Hugo De Vries(c) Herbert Spencer(d) Carl Linnaeus
Answer: (a)
6. Iodised salt is useful for men because it(a) Improves digestion(b) Increases resistance to diseases(c) Controls the thyroid gland(d) Slows down ageing process
Answer: (a)
7. In which layer of the atmosphere do most weather phenomena occur?(a) Exosphere(b) Stratosphere(c) Ionosphere(d) Troposphere
Answer: (d)
8. In the HINI Virus what does the alphabet H and N stands for: I H stands for haemagglutinin II N stands for neuraminidase(a) Only I is correct(b) Only II is correct(c) Both are correct(d) Both are incorrect
Answer: (c)
9. In the context of genetic disorders, consider the following:A woman suffers from colour blindness while her husband does not suffer from it. They have a son and a daughter. In this context, which one of the following statements is most probably correct? [UPSC 2009(CS-P)] (a) Both children suffer from colour blindness.(b) Daughter suffers from colour blindness while son does not suffer from it.(c) Both children do not suffer from colour blindness.(d) Son suffers from colour blindness while daughter does not suffer from it.
Answer: (d)
10. In the context of CO2 emission and Global Warming, what is the name of a market driven device under the UNFCC that allows developing countries to get funds/incentives from the developed countries to adopt, better technologies that
Answer: (b)
reduce greenhouse gas emissions? [UPSC 2009(CS-P)](a) Carbon Footprint(b) Carbon Credit Rating(c) Clean Development Mechanism(d) Emission Reduction Norm
11. In the context of alternative sources of energy, ethanol as a viable bio-fuel can be obtained from [UPSC 2009(CS-P)] (a) Potato(b) Rice(c) Sugarcane(d) Wheat
Answer: (c)
12. In making the saffron spice, which one of the following parts of the plant is used? [UPSC 2009(CS-P)] (a) Leaf(b) Petal(c) Sepal(d) Stigma
Answer: (d)
13. In higher pair, the relative motion is(a) Purely turning(b) Purely sliding(c) Purely rotary(d) Combination of sliding and turning
Answer: (d)
14. In an atom no two electrons have all the four quantum numbers identical. This is known as(a) Paulis Exclusion principle(b) Hunds Rule(c) Aufbau Principle(d) Avogadros Law
Answer: (a)
15. In a dry cell (battery), which of the following are used as electrolytes? [UPSC 2009(CS-P)](a) Ammonium chloride and Zinc chloride(b) Sodium Chloride and Calcium chloride(c) Magnesium chloride and Zinc chloride(d) Ammonium chloride and Calcium chloride
Answer: (a)
16. If the radius of the earth were to shrink by 1 %, its mass remaining the same, the value of 'g' on the earth's surface would(a) increase by 0.5%(b) increase by 2%(c) decrease by 0.5%(d) decrease by 2%
Answer: (b)
17. Galvanised Iron sheets have a coating of(a) Tin(b) Lead(c) Zinc(d) Chromium
Answer: (c)
18. Fruit most suitable for making jelly is________.(a) Papaya (b) Karunda(c) Mango (d) Banana
Answer: (c)
19. Epicenter of an earthquake is a point associated with the(a) place where earthquake is felt
Answer: (c)
(b) place of origin of earthquake in the interior of earth(c) point on the earth's surface just above seismic focus(d) point over the earth's surface where first shock is felt
20. Endoplasmic reticulum is bound by(a) Cellulose wall(b) Membranes(c) Sclerotised layer(d) Chitinised wall
Answer: (b)
21. Electric current is measured by(a) Voltmeter(b) Anemometer(c) Commutator(d) Ammeter
Answer: (d)
22. Dim-vision in the evening and night results from the deficiency of which one of the following?(a) Vitamin A(b) Vitamin E(c) Vitamin B12(d) Vitamin C
Answer: (a)
23. Diffusion of light in the atmosphere takes place due to(a) Carbon dioxide(b) Dust particles(c) Helium(d) Water vapours
Answer: (b)
24. Dental caries are due to(a) Viral infection(b) Contaminated water(c) Bacterial infection(d) Hereditary causes
Answer: (c)
25. Consider the following statements:1. Dinosaurs roamed the earth during the Mesozoic era.2. All Dinosaurus and other reptiles such as Ichthyosaurus and Pterosaurus. became extinct due to unknown reasons in Triassic period. Which of the statements above given is / are correct?(a) 1 only (b) 2 only(c) Both 1 and 2(d) Neither 1 nor 2
Answer: (a)
26. Consider the following statements:1.Cigarette smoking exposes a person to benzene.2.Benzene is known carcinogen.Which of the statements given above is / are correct?(a)1 only(b)2 only(c)Both 1 and 2(d) Neither 1 nor 2
Ans (c)
27. Consider the following statements:1. Sweet orange plant is propagated by grafting technique.2. Jasmine plant is propagated by layering technique.Which of the statements given above is/are correct? [UPSC 2009(CS-P)](a) 1 only(b) 2 only(c) Both 1 and 2(d) neither 1 nor 2
Answer: (c)
28. Consider the following:1. Camphor2. Chicory3. VanillaWhich of the above is/are plant product(s)? [UPSC 2009(CS-P)](a) 1 and 2 only(b) 3 only(c) 1 and 3 only(d) 1, 2 and 3
Answer: (d)
29. 'Bottle neck inflation' means(a) No rise in prices despite increase in aggregate demand(b) Rise in prices without increase in the aggregate demand(c) Decline in prices due to increase in aggregate demand(d) None of these
Answer: (b)
30. Biological Oxygen Demand (BOD) is used as a standard measure of________.(a) Oxygen level in forest system(b) Oxygen level in animals(c) Oxygen level in water system(d) Oxygen level in atmosphere
Answer: (c)
31. An eclipse of the Sun takes place(a) Once in every year(b) When the moon is full(c) When the moon passes between the sun and the earth(d) When earth comes between the sun and the moon
Answer: (c)
32. Among the following, the richest source of protein is(a) Ground Nut(b) Rice(c) Potato(d) Apple
Answer: (a)
33. All electioneering campaigns during the time of elections are stopped.(a) 48 hours before the appointed time of election results(b) 48 hours before the actual poll(c) 24 hours before the actual poll(d) 36 hours before the actual poll
Answer: (d)
34. AIDS stands for(a) Acquired Immune Disease Syndrome(b) Acquired Immunity Deficient Syndrome(c) Acquired Immune Deficiency(d) Acquired Infection Deficiency Syndrome
Answer: (c)
35. Activity of brain is recorded by(a) ECG(b) EEG(c) MET(d) CT
Answer: (b)
36. Acquired Immune Deeiciency Syndrome (AIDS) is caused by(a) bacterium(b) protozoa(c) fungus(d) virus
Answer: (d)
37. A term associated with the comparison of processing speed is(a) FFTS(b) MPG(c) MIPS
Answer: (c)
(d) CPS
38. A plant leaf appear to green because it(a) absorbs green light(b) relfects all but yellow and green light(c) reflect green light(d) absorbs red and yellow light
Answer: (c)
39. A periscope works by the principle of(a) Refraction(b) Total Internal reflection(c) Diffraction(d) Reflection and refraction
Answer: (b)
40. A mixure of solid Al2O3 and Fe2O3 can be separated by the method of(a) Forth floatation(b) Magnetic separation(c) Gravity separation(d) Dissolving in Water
Answer: (b)
41. A hollow cylindrical rod is filled with air, to make it a resonance column. To produce a wave of length 48 cm the minimum length of rod should be(a) 12 cm(b) 24 cm(c) 48 cm(d) 96 cm
Answer: (b)
42. Which of the following is most likely to cause a rise in the average temperature of the Earth in the future?(a) Atomic warfare(b) CO2 from fossil fuels(c) Dust clouds from volcanoes(d) Depletion of the Earth’s Ozone layer
Answer: (b)
43. A healthy freshwater fish is placed in saltwater. The expected consequence of this would be that(a) the fish becomes dehydrated and dies(b) the fish becomes bloated and dies(c) the fish suffers from fungal or bacterial disease and dies(d) ther is no observable effect on the fish provided there is sufficient food
Answer: (a)
44. A difference of 1 degree in longitude at the Equator is equivalent to nearly (a) 101 km(b) 111 km (c) 121 km(d) 125 km
Answer: (b)
45. A cell cycle consists of(a) mitosis and meiosis(b) G1, the S phase, and G2(c) Prophase, metaphase, anaphase and telophase(d) Interphase and mitosis
Answer: (d)
46. Which of the following poses the greatest safety risk when heated in laboratory?(a) A mixture of iron and sulfur(b) mercury(II) oxide(c) Sodium chloride(d) Copper(II) sulfate hydrate
Answer: (b)
47. A boy has five resistance of 1/5 ohm each. The maximum resistance that can be formed with them is(a) 0.5 ohm
Answer: (b)
(b) 1 ohm (c) 1/25 ohm(d) 1/5 ohm
48. A bat is(a) a mammal(b) a reptile(c) an amphibian(d) an avian
Answer: (a)
49. A "clinical death" take place when(a) there is no pulse(b) there is no heart beat(c) pupils are fixed and dilated, and there is no reaction to light(d) all the three conditions are present together
Answer: (d)
50. ______ based Institute of Genomics and INtegrative Biology, on December 8, 2009, announced to have succeeded in completely sequencing the genome of an individual.(a) Hyderabad(b) Nasik(c) Jaipur(d) New Delhi
Answer: (d)
Sr. No. Questions Answers
1. Vacuoles are bound by a definite membrane in plant cells called(a) Plasma membrane(b) Tonoplast(c) Cell wall(d) None of the above
Answer: (b)
2. Titan is the largest natural satellite of planet(a) Mercury(b) Venus (c) Saturn(d) Neptune
Answer: (c)
3. Thermometer is related to degree in the same way as clock is related to(a) Wall(b) Tower(c) Hour(d) Cock
Answer: (c)
4. There are rings around which of the following?(a) Uranus(b) Mars(c) Jupiter(d) Saturn
Answer: (d)
5. There are how many strains of H & N proteins that cumulatively make up the HN breed of flu virus (eg. being the presently famous H1N1 virus)(a) 16 & 9 respectively(b) 9 & 16 respectively(c) 16 & 16 respectively(d) 9 & 9 respectively
Answer: (a)
6. The wonder pigment chlorophyll is present in(a) Mitochondria(b) Centrosomes
Answer: (c)
(c) Quantosomes(d) Lysosomes
7. The vestiges of hind limbs are present in(a) Cobra(b) Sea snake(c) Krait(d) Python
Answer: (d)
8. The use of which of the following devices has given the modern biologist a better insight into the internal structure of cells(a) Computer(b) Electron microscope(c) Spectrophotometer(d) Ultracentrifuge
Answer: (b)
9. The two diseases that most often kill AIDS victims are1.Kaposi's sarcoma2.Lymphangioma3.Pneumocystis carinii pneumonia4.Systemic Lupus erythromatosus(a) 1 and 2(b) 2 and 3(c) 1 and 3(d) 3 and 4
Answer: (c)
10. The theory which advocates that living beings can arise only from other living beings is termed(a) Bio-genesis(b) Abiogenesis(c) Catastrophism(d) Cosmozoic
Answer: (a)
11. The theory that all animals and plants are made up of cells and they could arise only from pre-existing cells was propounded by(a) Robert Hooke(b) Matthias Schleiden and Theodore Schwann(c) Purkinje(d) Leuwenhoek
Answer: (b)
12. The theory of use and disuse was used to explain evolution by(a) Lamarck(b) Darwin(c) De Vries(d) Wallace
Answer: (a)
13. The terms Lubb and Dubb relate to which one of the following?(a) Heart(b) Eyes(c) Teeth(d) Lungs
Answer: (a)
14. The term 'epicentre' is associated with(a) Earthquakes(b) Tornadoes(c) Cyclones(d) Earth's interior
Answer: (a)
15. The speed of light with the rise in the temperature of the medium(a) Increases(b) Decreases(c) Remains unaltered
Answer: (c)
(d) Drops sharply
16. The solenocytes of Platyhelminthes, the nephridium of Annelids, and the kidneys of Vertebrates all have a similar function of excretion by differ in origin. They are said to be(a) Analogous(b) Homologous(c) Adaptational(d) Vestigeal
Answer: (a)
17. The solar eclipse occurs when(a) the sun comes in between the moon and the earth(b) the earth comes in the between the sun and the moon(c) the moon comes in between the sun and the earth(d) None of these
Answer: (c)
18. The smallest functional and structural unit of kidney is called as(a) Neuron(b) Nephron(c) Granulocyte(d) Reticulocyte
Answer: (b)
19. The removal of top soil by water or wind is called(a) Soil wash(b) Soil erosion(c) Soil creep(d) Silting of soil
Answer: (b)
20. The power of lens is - 2D. What is its focal length?(a) 2m(b) 0.5m(c) 1.0m(d) 0.5m
Answer: (d)
21. The Panda belongs to the same family as that of [UPSC 2009(CS-P)](a) Bear(b) Cat(c) Dog(d) Rabbit
Answer: (a)
22. The oxide of Nitrogen used in medicine as anaesthetic is(a) Nitrogen dioxide(b) Nitric oxide(c) Nitrous oxide(d) Nitrogen pentoxide
Answer: (d)
23. The modern synthetic theory of organic evolution is a synthesis of theories proposed by(a) Lamarck and Darwin(b) Lamarck and De Vries(c) Darwin and De Vries(d) None of the above
Answer: (c)
24. The marine animal called dugong which is vulnerable to extinction is a/an[UPSC 2009(CS-P)](a) Amphibian(b) Bony fish(c) Shark(d) Mammal
Answer: (d)
25. The leaf blight of paddy is caused by(a) Bacteria
Answer: (a)
(b) Virus(c) Nematodes(d) Fungus
26. The intencity of Earthquakes is measured on(a) Richter scale(b) Secant scale(c) Mercalli scale(d) Beaufort scale
Answer: (a)
27. The injection of anti-toxin is given to prevent(a) Tetanus(b) Tuberculosis(c) Typhoid(d) Filariasis
Answer: (a)
28. The hardest substance available on earth is(a) Platinum(b) Diamond(c) Quartz(d) gold
Answer: (a)
29. The general direct flow of summer monsoon in India is________.(a) From South to North(b) From South West to South East(c) From South East to South West(d) From South West to North East
Answer: (b)
30. The gas predominantly responsible for global warning is(a) Carbon dioxide(b) Carbon monoxide(c) Nitrous oxide(d) Nitrogen peroxide
Answer: (a)
31. The dynamo is a device for converting(a) Heat energy into electrical energy(b) Mechanical energy into electrical energy(c) Magnetic energy into electrical energy(d) None of these
Answer: (b)
32. The disease diphtheria affects(a) Lungs(b) Intestine(c) Throat(d) Body joints
Answer: (c)
33. The concept of carbon credit originated from which one of the following?(a) Earth Summit, Rio de Janeiro(b) Kyoto Protocol(c) Montreal Protocol(d) G-8 Summit, Hciligendamm
Answer: (b)
34. The cell that lacks a nucleus is(a) Flame cell(b) Spermatozoan(c) Red blood corpuscles in man(d) White blood corpuscles
Answer: (c)
35. The blue colour of the clear sky is due to(a) Diffraction of light(b) Dispersion of light(c) Reflection of light
Answer: (b)
(d) Refraction of light
36. The animal which uses sounds as its 'eyes' is(a) Dog(b) Cat(c) Snake(d) Bat
Answer: (d)
37. Thalassaemia is a hereditary disease affecting________.(a) Blood (b) Lungs(c) Heart (d) Kidney
Answer: (a)
38. Stem cuttings are commonly used for re-growing(a) Cotton(b) Banana(c) Jute(d) Sugar Cane
Answer: (d)
39. Stainless steel is an example of(a) A metallic compound(b) A homogeneous mixture(c) A heterogeneous mixture(d) An inorganic compound
Answer: (a)
40. Spontaneous generation signifying the development of living organisms from nonliving has been termed(a) Biogenesis(b) Abiogenesis(c) Cosmozoic(d) Catastrophism
Answer: (b)
41. Spinach leaves are rich source of(a) Vitamin A(b) Iron(c) Carotene(d) Vitamin E
Answer: (b)
42. Small pox is caused by(a) Bacteria(b) Fungus(c) Virus(d) Algae
Answer: (c)
43. Silk is produced by(a) Egg of silkworm(b) Pupa of silkworm(c) Larva of silkworm(d) Insect itself
Answer: (c)
44. Select the one which is not a mixture(a) Air(b) Gasoline(c) LPG(d) Distilled water
Answer: (d)
45. Researchers from Columbia Initiative in Systems Biology recently discovered two genes, C/EPB and Stat3, responsible for the most aggressive forms of human _______.(a) Hepatitis B(b) AIDS
Answer: (d)
(c) Blood Cancer(d) Brain cancer
46. Regarding the atom of a chemical element, the magnetic quantum number refers to(a) orientation(b) shape(c) size(d) spin
Answer: (a)
47. 'Ratti' used by jewellers is obtained from seed of a(a) Gymnospermous plant(b) Angiospermous plant(c) Algae(d) Fungi
Answer: (b)
48. Polythene is industrially prepared by the polymerisation of________.(a) Methane (b) Styrene(c) Acetylene (d) Ethylene
Answer: (d)
49. Plant cells can usually be distinguished because only plant cells possess(a) Cell walls and mitochondria(b) Golgi bodies and central vacuoles(c) Cell walls and central vacuoles(d) Chromosomes and mitochondria
Answer: (c)
50. Persons with which blood group are called universal donors?(a) AB(b) A(c) O(d) B
Answer: (c)
Sr. No. Questions Answers
1. Workers of paint industry are exposed to which one of the following hazards?(a) Nickel pollution(b) Cadmium pollution(c) Strontium pollution (d) Lead pollution
Answer: (d)
2. With reference to the work of human kidney, consider the following statement: 1. After the waste is remove in the kidney, the clear blood is sent back through renal artery. 2. From Bowman's capsule, the filtered liquid passes through tiny tubes where much of the gluclose is reabsorbed and sent back to the blood in the renal vein. Which of the following is/are correct?(a) Only 1.(b) Only 2.(c) Both 1 & 2(d) Neither 1 nor 2
Answer: (d)
3. With reference to the evolution of living organisms, which one of the following sequences is correct? [UPSC 2009(CS-P)](a) Octopus - Dolphin - Shark(b) Pangolin - Tortoise - Hawk(c) Salamander - Python - Kangaroo(d) Frog - Crab - Prawn
Answer: (c)
4. With reference to normal human beings consider the following statements:1. In response to the presence of HCL, secretin is produced from the duodenum.2. Enterogastrone is produced in the small intestine in response to the presence of
Answer: (c)
fatty acids.Which of the statements is/are correct?(a) Only 1(b) Only 2(c) Both 1 & 2(d) Neither 1 nor 2
5. Winds and air currents differ in the aspect that(a) air currents blow much faster than winds(b) air currents are always moisture laden while winds are usually dry(c) the winds blow on lands while air currents blow over seas and oceans(d) winds are horizontal movements of air while air currents are the vertical movements of air
Answer: (d)
6. WiMAX is related to which one of the following? [UPSC 2009(CS-P)](a) Biotechnology(b) Space technology(c) Missile technology(d) Communication technology
Answer: (d)
7. Why is it difficult to see through fog?(a) Rays of light suffer total internal reflection from the fog droplets(b) Rays of light are scattered by the fog droplets(c) Fog droplets absorb light(d) The refractive index of fog is extremely High
Answer: (b)
8. Who was the first scientist to use an instrument for biological studies in 1665?(a) Robert Hooke(b) Schwann(c) Schleiden(d) None of the above
Answer: (a)
9. Who of the following scientists proved that the stars with mass less than 1.44 times the mass of the Sun end up as White Dwarfs when they die? [UPSC 2009(CS-P)](a) Edwin Hubble(b) S. Chandrashekhar(c) Stephen Hawking(d) Steven Weinberg
Answer: (b)
10. Who gave the first evidence of the Big- Bang theory?(a) Edwin Hubble(b) Albert Einstein(c) S. Chandrasekhar(d) Stephen Hawking
Answer: (a)
11. Which onr the following is the most effective carrier for communications?(a) Cables(b) Microwaves(c) Optical fibres(d) Radiowaves
Answer: (b)
12. Which one of the following types of waves are used in a night vision apparatus?[UPSC 2009(CS-P)](a) Radio waves(b) Microwaves(c) Infra-red waves(d) None of the above
Answer: (c)
13. Which one of the following statement is NOT correct?(a) Milk contains none of the B-vitamins(b) Vitamin-A (retinal) deficiency leads to dry and scaly skin(c) One of the symptoms of scurvy is pain in the joints
Answer: (a)
(d) Vitamin-B, (thiamine) deficiency can lead to heart failure
14. Which one of the following planets has largest number of natural satellites or moons?(a) Jupiter(b) Mars(c) Saturn(d) Venus
Answer: (a)
15. Which one of the following is used as an explosive? [UPSC 2009(CS-P)](a) Phosphorus trichloride(b) Mercuric oxide(c) Graphite(d) Nitroglycerine
Answer: (d)
16. Which one of the following is responsible for blue baby syndrome?(a) Fluoride(b) Nitrate(c) Arsenic(d) Lead
Answer: (b)
17. Which one of the following is not a radioactive element?(a) Uranium(b) Radium(c) Thorium(d) Cadmium
Answer: (d)
18. Which one of the following is correct?A concrete wall generally,(a) only reflects sound(b) only absorbs sound(c) only transmits sound(d) absorbs and transmits sound
Answer: (d)
19. Which one of the following is considered as the easily digestible source of protein?(a) Egg albumin(b) Soybean(c) Fish flesh(d) Red meat
Answer: (b)
20. Which one of the following is a water soluble vitamin?(a) Vitamin A(b) Vitamin C(c) Vitamin D(d) Vitamin K
Answer: (b)
21. Which one of the following is a viral disease transmitted to man by the bite or rabid animals particularly dogs?(a) Cholera(b) Plague(c) Malaria(d) Rabies
Answer: (d)
22. Which one of the following groups of animals are primates?(a) Giraffes and Zebras(b) Kangaroos and Koalas(c)Lemurs and Lorises(d) Rabbits and Hares
Answer: (c)
23. Which one of the following glands produces the Growth Hormone (Somatotropin)?(a) Adrenal(b) Pancreas
Answer: (c)
(c) Pituitary(d) Thyroid
24. Which one of the following gases is predominant in the atmosphere?(a) Argon(b) Nitrogen(c) Carbon Dioxide(d) Oxygen
Answer: (b)
25. Which one of the following diagrams shows the direction and duration of wind?(a) Cartogram(b) Climognim(c) Ergograph(d) Star diagram
Answer: (d)
26. Which one among the following kinds of organisms resides in the roots of pulse Plants to do nitrogen fixation?. (a) Bacteria(b) Fungi(c) Protozoa(d) Virus
Answer: (a)
27. Which one among the following has the highest energy? [UPSC 2009(CS-P)](a) Blue light(b) Green light(c) Red light(d) Yellow light
Answer: (a)
28. Which of these is not a mosquito borne disease?(a) Dengue fever(b) Malaria(c) Filariasis(d) Goitre
Answer: (d)
29. Which of the following vitamins helps in the absorption of calcium?(a) Vitamin A(b) Vitamin B(c) Vitamin C(d) Vitamin D
Answer: (d)
30. Which of the following uses non-conventional Source of Energy?(a) Kerosene lamp(b) Wax candle(c) Solar lantern(d) Torch
Answer: (c)
31. Which of the following plant diseases is caused by a virus?(a) Aster yellows(b) Barley yellow dwarf(c) Curly top of sugar beets(d) All of the above
Answer: (d)
.32. Which of the following planets rotates clock wise?(a) Pluto(b) Jupiter (c) Venus(d) Mercury
Answer: (c)
33. Which of the following order is given to the plantes of solar system on the basis of their sizes?(a) Jupiter, Saturn, Earth, Mercury(b) Saturn, Jupiter, Mercury, Earth
Answer: (a)
(c) Mercury, Earth, Jupiter, Saturn(d) Earth, Mercury, Saturn, Jupiter
34. Which of the following is suitable for growing cotton?(a) Sandy soil(b) Clayey soil(c) Black soil(d) Alluvial soil
Answer: (c)
35. Which of the following is not a natural fibre(a) Silk(b) Jute(c) Coir(d) Rayon
Answer: (d)
36. Which of the following is a water -borne diseases?(a) Viral hepatitis B(b) Cholera(c) Dengu(d) Influenza
Answer: (b)
37. Which of the following has been found useful in keeping cholesterol level down(a) Tulsi(b) Serpentina(c) Turmeric(d) Garlic
Answer: (d)
38. Which of the following crops is of Kharif season?(a) Soyabean (b) Linseed(c) Lentil (d) Mustard
Answer: (a)
39. Which of the following can be used to control the speed of a D. C. motor?(a) Thermistor(b) Thyristor(c) Thyratron(d) Transistor
Answer: (b)
40. Which acid is produced when milk gets sour?(a) Tartaric acid(b) Butyric acid(c) Lactic acid(d) Acetic acid
Answer: (c)
41. When the earth was formed it had an atmosphere with(a) Hydrogen, Oxygen and Nitrogen(b) Water vapour, Hydrogen and Oxygen(c) Oxygen, Carbondioxide and Nitrogen(d) Water vapour, Ammonia and Methane.
Answer: (d)
42. When an ant bites a person, which irritating chemical it (ant) injects into his (person) body?(a) Acetic acid(b) Citric acid(c) Tartaric acid(d) Formic acid
Answer: (d)
43. When 1 litre of water freezes, the volume of ice formed will be(a) 0.9 litre(b) 1.0 litre(c) 1.11 litre
Answer: (c)
(d) 1.5 litre
44. What would be the best choice for window material to keep the outside heat away?(a) Single-pane glass(b) Double-pane glass without a gap in between(c) Double-pane glass with water filled in between(d) Double-pane glass with air in between
Answer: (d)
45. What is the bacterial disease in lime fruits?(a) Phytophthora(b) White rust(c) Citrus canker(d) Smut disease
Answer: (c)
46. Water boils at a lower temperature on the hills because(a) It is cold on the hills(b) There is less carbon dioxide on the hills(c) There is a decrease in air pressure on the hills(d) there is less oxygen
Answer: (c)
47. Washing soda is the common name for(a) Calcium carbonate(b) Calcium bicarbonate(c) Sodium carbonate(d) Sodium bicarbonate
Answer: (c)
48. Vitamin concerned with vision is(a) Vitamin A(b) Vitamin B1(c) Vitamin B2(d) Vitamin B6
Answer: (a)
49. Vestigeal pelvic girdle and bones of hind limbs are characteristic of(a) Whales(b) Dolphins(c) Seals(d) Sharks
Answer: (a)
50. Vestigeal organs are those which are(a) Fully formed and functional(b) Much reduced but functional(c) Much reduced and functionless(d) Fully formed but functionless
Answer: (c)
Sr. No. Questions Answers
1. The scientist who is known as father of modern biology is(a) B. F. Skinner(b) Aristotle(c) Wilhelm Wundt(d) Archimedes
Answer: (b)
2. The science of weights and measures is called:(a) metrology(b) meteorology(c) mineralogy(d) morphology
Answer: (a)
3. The point at which solid, liquid and gaseous forms of a substance co-exist is called(a) sublimation point(b) distillation point(c) triple point
Answer: (c)
(d) melting point
4. The persons working in textile factories such as carpet weavers are exposed to which of the following occupational disease?(a) Asbestosis(b) Asthma and Tuberculosis(c) Silicosis(d) Siderosis
Answer: (b)
5. The parachute was used for the first time by(a) Max Born(b) Francis Crick(c) J.P.Blanchard(d) Enrico Fermi
Answer: (c)
6. The only species of cat that lives and hunts in groups is(a) lion(b) leopard(c) jaguar(d) cougar
Answer: (a)
7. The most abundant organic molecule on the surface of the Earth is:(a) cellulose(b) chitin(c) DNA(d) hemoglobin
Answer: (a)
8. The law of gravitation was propounded by(a) Alfred Binet(b) Alfred Kinsey(c) Sir Isaac Newton(d) Alexander Fleming
Answer: (c)
9. The launch of the first LIQUID fueled rocket in the world is attributed to:(a) China(b) Russia(c) United States(d) Germany
Answer: (c)
10. The instrument used to measure the relative humidity of air is(a) Hygrometer(b) Salinometer(c) Calorimeter(d) Hydrometer
Answer: (a)
11. The instrument used to measure the pressure of gases is the(a) Barometer(b) Monometer(c) Psychrometer(d) Spectrophotometer
Answer: (b)
12. The instrument used to measure the concentration of salt water is the(a) Galvanometer(b) Salinometer(c) Altimeter(d) Hygrometer
Answer: (b)
13. The German physicist who first demonstrated the existence of Radio waves was(a) Arthur Eddington(b) Henrich Hertz(c) William Harvey(d) Marcello Malpighi
Answer: (b)
14. The first person to see a cell under microscope was(a) Max von Laue(b) Gustav Kirchhoff(c) Robert Hooke(d) Hans Bethe
Answer: (c)
15. The fastest-running terrestrial animal is(a) cheetah(b) lion(c) man(d) jaguar
Answer: (a)
16. The density of milk is measured by a(a) Monometer(b) Hygrometer(c) Lactometer(d) Anemometer
Answer: (c)
17. The characteristic odour of Garlic is due to which one of the following?(a) Chlorine-containing compounds(b) Fluorine-containing compounds(c) Nitrogen-containing compounds(d) Sulphur-containing compounds
Answer: (d)
18. The branch of medical science which is concerned with the study of disease as it affects a community of people is called(a) epidemiology(b) oncology(c) paleontogy(d) pathology
Answer: (a)
19. The angle between the geographical meridian and magnetic meridian is called(a) Angle of dip(b) Angle of declination(c) Angle of inclination(d) None of the above
Answer: (b)
20. Superconductivity is a material property associated with(a) cooling a substance without a phase change(b) frictionless liquid flow(c) a loss of thermal resistance(d) a loss of electrical resistance
Answer: (d)
21. Pollination by birds is called(a) autogamy(b) ornithophily (c) entomophily (d) anemophily
Answer: (b)
22. Mist is caused bya) Dry iceb) Ice at low temperaturec) Water vapours at low temperatured) Carbon- monoxide in solid form
Answer: (c)
23. Match List-I with List-II and select the correct answer using the code given below the Lists: List-I List-II Celestial Body) ( Roman God)A. Mercury 1. God of the Under world and DeathB. Pluto 2. God of Commerce, Eloquence and SkillC. Mars 3. God of the Sea
Answer: (d)
D. Neptune 4. God of WarCode:(a) A B C D 3 1 4 2(b) A B C D 2 4 1 3(c) A B C D 3 4 1 2(d) A B C D 2 1 4 3
24. In the human body, Cowper’s glands form a part of which one of the following?(a) Digestive system(b) Endocrine system(c) Reproductive system(d) Nervous system .
Answer: (c)
25. In normal adult human, what is the rate of heartbeat per minute?(a) 72-80(b) 70-75(c) 80-97(d) 82-87
Answer: (a)
26. In human body, what is the number of cervical vertebrae?(a) 5(b) 7(c) 8(d) 12
Answer: (b)
27. In daylight the human eye is most sensitive to which color?(a) Green(b) Red(c) Blue(d) Orange
Answer: (a)
28. If a metal can be drawn into wires relatively easily it is called(a) malleable(b) ductile(c) extractive(d) tactile
Answer: (b)
29. Evaporation from water surfaces exposed to air is not dependent of the:(a) velocity of the wind(b) humidity(c) temperature(d) depth of the water
Answer: (d)
30. Earth quake waves travel fastest in(a) Soil(b) Molten rock(c) Water(d) Flexible rock
Answer: (c)
Sr. no. Questions Answers
1. Yeast, used in making bread is a:(a) plant(b) fungus(c) bacteria(d) seed
Answer: (b)
2. Who was the marine biologist and author of Silent Spring who was one of the first Answer: (b)
people to warn of the dangers of pesticides like DDT?(a) Jacques Cousteau(b) Rachel Carson(c) Charles Darwin(d) Marlin Perkins
3. Who was the first scientist credited with pointing out that certain gases could cause a greenhouse effect?(a) John Tyndall(b) Charles Darwin(c) Roger Tory Peterson(d) Stephen Jay Gould
Answer: (a)
4. Who is known as the Father of the Atomic Bomb?(a) Albert Einstein(b) J. Robert Oppenheimer(c) General Leslie Groves(d) Edward Teller
Answer: (b)
5. Who is called the Father of the Nuclear Navy?(a) Edward Teller(b) Robert Oppenheimer(c) Hymen Rickover(d) Chester Nimitz
Answer: (c)
6. Which of the following seeds will normalize blood sugar level?(a) Coriander(b) Mustard(c) Cumin(d) Fenugreek
Answer: (d)
7. Which of the following plants is not capable of manufacturing own food?(a) Algae(b) Mushroom(c) Carrot(d) Cabbage
Answer: (b)
8. Which of the following nutrients is not a structural component of the plant?(a) Nitrogen(b) Calcium(c) Phosphorus(d) Potassium
Answer: (b)
9. Which of the following is primarily composed of calcium carbonate?(a) Fish scales(b) Shark teeth(c) Oyster Shells(d) Whale bones
Answer: (c)
10. Which of the following is not a property of difference amplifier?(a) Capacitor is used in it(b) It is used to compare two signals(c) Difference amplifier yields more than the direct couple ampliier(d) Frequency of difference amplifier remains flat from zero to high frequency
Answer: (a)
11. Which of the following is a rich source of energy?(a) Protein{b) Lipid(c) Carbohydrate(d) Vitamin
Answer: (b)
12. Which of the following is a cellulose fiber? Answer: (a)
(a) Cotton(b) Wool(c) Rayon(d) Polyester
13. Which of the following gases is released from rice fields in the most prominent quantities?(a) Carbon dioxide(b) Methane(c)Carbon monoxide(d) Sulphur dioxide
Answer: (b)
14. Which colour of heat radiation represents the highest temperature?(a) Blood red(b) Dark cherry(c) Salmon(d) White
Answer: (d)
15. Which among the following substances is used as a lubricant?(a) Quartz(b) Silica(c) Graphite(d) Nickel
Answer: (c)
16. What power cycle is used in jet engines?(a) Stirling(b) Rankine(c) Otto(d) Brayton
Answer: (d)
17. What is the pH value of pure water?(a) 1(b) 6(c) 7(d) 10
Answer: (c)
18. What is Jeweller’s rouge?(a) Ferric oxide(b) Ferrous oxide(c) Ferrous carbonate(d) Ferric carbonate
Answer: (a)
19. What is “H5N1″ a term , which was very much in news recently ?(a) It is a category of Visa provided by the USA fOR STUDENTS.(b) It is the name of the virus which cause Bird flu(c) It is the code name of India’s space Mission 2010.(d) It was the name of the military operation launched by Sri Lanka against LTTE.
Answer: (b)
20. What form of radiation most closely resembles X-rays?(a) alpha(b) beta(c) gamma(d) neutron
Answer: (c)
21. What does airbag, used for safety of car driver, contain?(a) Sodium bicarbonate(b) Sodium azide(c) Sodium nitrite(d) Sodium peroxide
Answer: (b)
22. Water flows through a horizontal pipe at a constant volumetric rate.At a location where the cross sectional area decreases, the velocity of the fluid:
Answer: (a)
(a) increases(b) decreases(c) stays the same
23. The word atom is from a Greek word meaning:(a) small(b) indivisible(c) unseen(d) visible
Answer: (b)
24. The weight of an object will be minimum when it is placed at(a) The North Pole(b) The South Pole(c) The Equator(d) The center of the Earth
Answer: (d)
25. The uranium fuel used worldwide is mainly in the form of:(a) U3O8(b) UO2(c) UF6(d) U metal
Answer: (b)
26. The time taken by the Sun to revolve around the center of our galaxy is(1) 50 mn years(2) 100 mn years(3) 250 mn years(4) 365 mn years
Answer: (c)
27. The theory of relativity was brought forward by(a) Louis Victor de Broglie(b) Albert Einstein(c) Carl Linnaeus(d) Jean Piaget
Answer: (b)
28. The study of phenomena at very low temperatures is called(a) heat transfer(b) morphology(c) crystallography(d) cryogenics
Answer: (d)
29. The study of how people use tools to perform work and how people physically relate to their working environment is called(a) engineering(b) ergonomics(c) agronomy(d) physiology
Answer: (b)
30. The Statue of Liberty is green because of:(a) green stone(b) oxidized brass(c) steel painted green(d) oxidized copper
Answer: (d)
1. Who invented the telephone?(a) Thomas Alva Edison(b) Galileo(c) Alexander Graham Bell(d) G. Marconi
Answer: (c)
2. Who invented the railway engine?(a) Charles Babbage (b) Isaac Newton
Answer: (d)
(c) James Watt (d) George Stephenson
3. Who invented Radar?(a) Henrey Backquerel(b) Max Planck (c) Robert Watson Watt(d) Humphrey Davy
Answer: (c)
4. Who invented polio vaccine (oral)?(a) Albert Sabin (b) Burkholder (c) Luise Pasture (d) Jonas Salk
Answer: (a)
5. Who developed the small pox vaccination? (a) Eduard Jenner (b) Alexander Fleming (c) Albert Einstein (d) None of these
Answer: (a)
6. Which one of the following was to be discovered first in the chromosphere of the sun(a) Helium(b) Neon(c) Xenon(d) Krypton
Answer: (a)
7. Which famous inventor ranks second in the number of patents registered?(a) Thomas Alva Edison(b) James Watt(c) Albert Einstein(d) Edwin Land
Answer: (d)
8. What famous scientist and inventor participated in the invention of the Aqua-Lung?(a) Thomas Edison(b) Isaac Newton(c) Leonardo da Vinci(d) Jacques Cousteau
Answer: (d)
9. Vulcanised rubber was invented by(a) Charles Goodyear(b) William Stockes(c) J.E.Lundstrom(d) Sir Joseph Swann
Answer: (A)
10. The system for writing by blind people was invented by(a) Louis Braille(b) Henry Bacquerel(c) Sir J.A.Fleming(d) Dr.Charles H. Townes
Answer: (a)
11. The steam engine was invented by(a) William Stockes(b) J.E.Lundstrom(c) Sir Joseph Swann(d) James Watt
Answer: (D)
12. The steam engine was invented by(a) James Watt(b) James Prescott Joule(c) New Commen
Answer: (a)
(d) Isaac Newton
13. The revolver was invented by(a) Eduard Jenner (b) Alexander Fleming (c) Albert Einstein(d) Samuel Colt
Answer: (d)
14. The refrigerator was invented by(a) J.Perkins(b) Alexander Fleming (c) Albert Einstein (d) Benjamin Franklin
Answer: (a)
15. The nuclear reactor was invented by(a) Enrico Ferni(b) Eduard Jenner (c) Alexander Fleming (d) Albert Einstein Torricelli
Answer: (a)
16. The laws of floating bodies was discovered by(a) Pierre Simon de Laplace(b) Archimedes(c) Edwin Hubble(d) Joseph J. Thomson
Answer: (b)
17. The four blood groups were discovered by(a) Richard Feynman(b) Karl Landsteiner(c) Alfred Wegener(d) Stephen Hawking
Answer: (b)
18. The existence of isotopes was discovered by(a) Emil Kraepelin(b) Trofim Lysenko(c) Frederick Soddy(d) Francis Galton
Answer: (c)
19. The electro-cardiograph was invented by(a) B. F. Goodrich(b) Gottlieb Daimler(c) Karl Benz(d) William Einthoven
Answer: (d)
20. Stethoscope was invented by(a) William Shockley(b) Tim Berners Lee(c) Chester Carlson(d) William Stockes
Answer: (d)
21. Spinning frame was invented by(a) Charles Macintosh(b) Antoine Joseph Sax(c) Samuel Morse(d) Sir Richard Arkwright
Answer: (d)
22. Sodium was discovered by(a) Sir Humphry Davy(b) James Watson(c) John Bardeen(d) John von Neumann
Answer: (a)
23. Safety matches was invented by(a) Levi Strauss(b) Benjamin Franklin(c) Peter Goldmark(d) J.E.Lundstrom
Answer: (d)
24. Rayon was invented by(a) Sir Joseph Swann(b) Adolph Rickenbacker(c) David Brewster(d) Christopher Cockerell
Answer: (a)
25. Radium was discovered by(a) Willard Libby(b) Edward Teller(c) Ernst Haeckel(d) Marie and Pierrie Curie
Answer: (d)
26. Radioactivity was discovered by(a) Karl Landsteiner(b) Konrad Lorenz(c) Henry Bacquerel(d) Edward O. Wilson
Answer: (c)
27. Radio valve was invented by(a) Sir J.A.Fleming(b) George Eastman(c) William Burroughs(d) Michael Faraday
Answer: (a)
28. Nylon was invented by(a) Dr.Wallace H.Carothers(b) Adolph Rickenbacker(c) David Brewster(d) Christopher Cockerell
Answer: (a)
29. Microscope was invented by(a) Aaton Van Leewen Hock(b) Robert Recorde(c) William Oughtred(d) Hermann Fottinger
Answer: (a)
30. Laser was invented by(a) Dr.Charles H. Townes(b) Edwin Hubble(c) Albert Einstein(d) S. Chandrasekhar
Answer: (a)
Everyday Science - One of the Countries through which equator passes is....
1) One of the countries through which equator passes is:
(a) Kenya(b) Malaysia(c) Malta(d) Pakistan
2) Copper can be converted into gold by:
(a) Artificial radioactivity(b) heating(c) Electroplating(d) Chemical reaction
3) The three elements needed for healthy growth of plants are:
(a) N, P, K(b) N, C, P(c) N, K,(d) N, S, P
4) Clocks, which moves with the velocities comparable with the velocity of light, run:
(a) fast(b) slow(c) equal to the velocity of light(d) with zero velocity
5) Max Planck received the noble prize in Physics in 1918 for his discovery of:
(a) electron(b) energy quanta(c) photon(d) positron
6) Bronze medal is made up of metals:
(a) (copper,nickel)(b) (copper, tin)(c) (copper, silver)(d) (copper, zinc)
7) Addison’s disease is caused by the excessive secretion of:
(a) Antiduretic Harmone(b) Luteinising Harmone(c) Melanophore stimulating Harmone(d) Adrenocorticotrophic Harmone
8) Development of calf muscles in ladies who wear high heels is a common example of:
(a) Natural Selection(b) inheritance of acquired character(c) Use and disuse of organ(d) Artificial selection
9) Margalla Hill is a branch of:
(a) Karakorum range(b) Hindukash range(c) Himalaya range(d) Nanga Parbat range
10) Humming bird belongs to a category called:
(a) Ectotherm(b) Endotherm(c) Exotherm(d) Heterotherm.
(a) Oxidation-Loss of an electron(b) Oxidation – gain of an electron(c) Reduction – gain of a neutron(d) Reduction – loss of a neutron
(2) Radioactive isotope of Uranium used in Nuclear Bomb is:
(a)92 U 235(b)92 U 234c)92 U 233d)92 U 238
(3) Human population growth is greatest in developing countries because:
(a) the birth rate is high in developing countries(b) the death rate is high in developing countries.(c) much of the population has already reached the child bearing age.(d) most of the world’s population lives in industrialized countries.
(4) Which woody raw material is used for the manufacture of paper pulp?
(a) Cotton(b) Poplar (c) Bagasse(d) Rice straw
(5) Rectified spirit contains alcohol about:
(a) 80%(b) 95% (c) 70%(d) 85%
(6) Which of the following elements is not present abundantly in earth’s crust:
(a) Silicon(b) Radium (c) Aluminum(d) Carbon
(7) The famous book; Al – Qanoun was written by the Muslim scientist:
(a.) Jabar bin Hayyan(b) Zakariya Al – Razi(c) Abu Ali Sina(d) Abdul Qasim Majreeti
(8) Basic metals can be converted into gold by:
(a) Heating(b) Beating(c) Artificial nuclear radioactivity(d) Chemical reaction
(9) A light year is a unit of:
(a) Time(b) Energy(c) Length(d) Mass
(10) One of the main function of the earth’s ozone layer is to:
(a) Prevent global warming(b) Filter out ultraviolet rays (c) Absorb pollution(d) All of the above
11. Insulin is injected into the intestines by
A. PancreasB. LiverC. StomachD. Gall bladder
12. Lock Jaw, i.e., difficulty in opening the mouth is a symptom of
A. CholeraB. PlagueC. TetanusD. Diphtheria
13. Which of the following pairs is incorrect?
A. Plague-ratsB. Rabies-dogC. Tapeworm-pigD. Poliomyelitis-monkey
14. Match the following columns
Column I Column II
A. Air-borne 1. TetanusB. Water-borne 2. TuberculosisC. Contact 3. CholeraD. Wound 4. Syphilis
A B C D
(a) 2 3 1 4
(b) 2 3 4 1
(c) 3 2 4 1
(d) 4 3 2 1
15. Ricketts is a disease of the
A. BonesB. TissueC. MusclesD. Blood
16. Which of the following statements is correct?
A. Pulmonary artery carries pure bloodB. Pulmonary artery carries impure bloodC. Pulmonary vein carries impure bloodD. None of these
17. Lungs are situated in the
A. Abdominal cavityB. Pericardial cavityC. Buccal cavityD. Thoracic cavity
18. The human cell contains
A. 44 chromosomesB. 48 chromosomesC. 46 chromosomesD. 23 chromosomes
19. Enzymes help in
A. RespirationB. Digestion of foodC. Immune systemD. Reproduction
20. Food is normally digested in the
A. LiverB. StomachC. Small intestinesD. Large intestines
11. a 12. c 13. d14. b 15. a16. b 17. d 18. c 19. b 20. C
26. Myopia is a disease connected with
A. EarsB. EyesC. LungsD. Brain
27. Leukemia is a disease of the
A. LungsB. BloodC. SkinD. Nerves
28. Short-sightedness can be corrected by using
A. Convex lensB. Concave lensC. Convex-concave lensD. Concave-convex lens
29. Trachoma is a disease of the
A. LiverB. EyesC. LungsD. Kidneys
30. Match the following
Column I Column II
A. Beriberi 1. Vitamin AB. Scurvy 2. Vitamin BC. Rickets 3. Vitamin CD. Night Blindness 4. Vitamin D
A B C D
(a) 3 2 1 4
(b) 2 1 3 4
(c) 2 3 4 1
(d) 2 3 1 4
31. Typhoid and cholera are typical examples of
A. Infectious diseasesB. Air-borne diseaseC. Water-borne diseaseD. None of these
32. Pyorrhea is a disease of the
A. NoseB. GumsC. HeartD. Lungs
33. Lack of what causes diabetes.
A. SugarB. InsulinC. CalciumD. Vitamins
34. Appendix is appendix is a part of
A. Small intestineB. Large intestineC. StomachD. Liver
35. Match the following columns
Column I Column II
A. Cataract 1. BonesB. Jaundice 2. EyesC. Diabetes 3. LiverD. Arthritis 4. Pancreas
A B C D
(a) 2 3 4 1
(b) 2 3 1 4
(c) 1 3 4 2
(d) 3 2 4 1
36. Bronchitis is a disease of which of the following organs?
A. BloodB. BladderC. LiverD. Respiratory tract
37. ECG is used for the diagnosis of aliments of
A. BrainB. HeartC. KidneysD. Lungs
38. Biopsy is done on
A. Tissues taken from a dead bodyB. Tissues taken form a living bodyC. Blood from veinsD. Blood from arteries
39. Barium is used for
A. Checking blood groupB. X-ray of alimentary canalC. X-ray of brainD. None of these
40. Dialysis is used for the treatment of
A. Kidney failureB. Heart weaknessC. Brain diseasesD. None of these
ANSWERS
26. b 27. b 28. b 29. b 30. c31. c 32. b 33. b 34. b 35. a36. d 37. b 38. b 39. b 40. a