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Biology

Single correct answer type: 1. One of the breeding techniques useful to eliminate harmful recessive genes by selection is (A) Artificial insemination (B) Outbreeding (C) Inbreeding (D) MOET Solution: (C) When breeding is done between animals of the same breed for 4-6 generations, it is called inbreeding. Inbreeding is necessary if we want to develop a pure line of any animal. It exposes harmful recessive genes that are eliminated by selection. It also helps in accumulation of superior genes and elimination of less desirable genes. 2. Herbicide that blocks electron transport from PS-II to PS-I by inhibiting electron flow between

plastoquinone cytochrome is (A) DCMU (B) Paraquat (C) DCPIP (D) None of these Solution: (A) DCMU is selective herbicide that acts as a potent inhibitor of PS-II. Paraquat inhibits PS-I by producing super oxides. DCPIP is a dye used to measure rate of photosynthesis. 3. Statement I Microtubules are formed only in animal cells. Statement II Microtubules are made up of a protein called myosin. Choose the correct option (A) Statement I is correct and statement II is incorrect. (B) Statement II is correct and statement I is incorrect. (C) Both statements are correct. (D) Both statements are incorrect. Solution: (D) Microtubules are found in both animal and plant cells and are formed of protein tubulin. 4. Some functions of nutrient element are given below

Important constituent of proteins involved in ETS. Activator of catalase. Important constituent of cytochrome.

Essential for chlorophyll synthesis. The concerned nutrient is

(A) (B)

(C) (D) Solution: (B) Iron is the concerned nutrient associated with the above given functions. 5. Torsion of visceral mass is seen in animals belonging to class

(A) Cephalopoda (B) Scaphopoda (C) Amphineura (D) Gastropoda Solution: (D) Animals of class-Gastropoda of phylum-Mollusca undergo twisting or torsion of the visceral mass during development, leading to conversion of symmetrical embryo into an asymmetrical adult.

6. A plant is provided with ideal conditions for photosynthesis and supplied with isotope When the products of the process are analysed carefully, what would be the nature of products? (A) Glucose and oxygen are labelled (B) Oxygen is labelled, but glucose is normal (C) Glucose and oxygen are normal (D) Glucose is labelled, but oxygen is normal Solution: (D) In the process of photosynthesis

→

Plants manufacture glucose from and and oxygen gas is released. So, due to isotopic carbon of only glucose will be labelled, but oxygen will be normal. 7. Match the following columns.

Column I Column II

Sacral nerves Pair

Thoraic nerves

pairs

Cocygeal nerves

Pairs

Cervical nerves

Pairs

Pairs Codes: (A) A – 4; B – 1; C – 3; D – 2 (B) A – 5; B – 3; C – 1; D – 2 (C) A – 5; B – 4; C – 1; D – 2 (D) A – 2; B – 5; C – 3; D – 1 Solution: (C) The correct matchings are

Sacral nerves Pairs

Thoraic nerves Pairs Cocygeal nerves 1 Pair

Cervical nerves Pairs 8. Pick the hormone which is not secreted by human placenta (A) hCG (B) hPL (C) Prolactin (D) Oestrogen

Solution: (C) Prolactin is secreted by pituitary gland, whereas the hCG, hPL and oestrogen are secreted by human placenta.

9. Fixation of one molecule through Calvin cycle requires. (A) ATP and

(B) ATP and (C) ATP and (D) ATP and Solution: (C)

ATP are required during conversion of PGA to 1, 3 diphosphoglyceric acid and ATP during conversion of glyceraldehyde phosphate to ribulose biphosphate. molecules are utilized for

converting diphosphoglyceric acid to glyceraldehyde phosphate. 10. Oxygen dissociation curve of haemoglobin is (A) Sigmoid (B) Hyperbolic (C) Linear (D) Hypobolic Solution: (A) Oxygen haemoglobin dissociation curve gives the relationship between the saturation of haemoglobin and oxygen tension.

The curve obtained by plotting the per cent saturation of against time is sigmoid, at and Dissociation of oxyhaemoglobin can be promoted by rise in the body temperature and low (high ). 11. A hormone, secreted by the endocrinal cells of duodenal mucosa which influences the release of pancreatic juice is (A) Relaxin (B) Cholecystokinin (C) Secretin (D) Progesterone Solution: (B) Cholecystokinin Pancreozymin (CCK-PZ) is the hormone secreted from mucosa of small intestine. It stimulates pancreas to release enzymatic (Pancreatic) juice and gall bladder to eject bile. 12. Cotyledons and testa are edible parts of (A) Ground nut and pomegranate (B) Walnut and Tamarind (C) French bean and coconut (D) Cashew nut and litchi Solution: (A) Cotyledons and testa are edible parts of ground nut and pomegranate respectively. The edible part of walnut is cotyledon, tamarind-mesocarp, french beans-seeds, coconut-endosperm testa, cotyledons and embryo, cashewnut-cotyledons and fleshy pedicels and of litchi is fleshy aril. 13. Intrinsic and extrinsic pathways of blood clotting are interlinked at the activation steps of which of the following factors? (A) Factor IX (B) Factor IV

(C) Factor X (D) Factor XIII-a Solution: (C) Both intrinsic and extrinsic pathway of blood clotting are interlinked at the final common pathway of factor X, thrombin and fibrin. 14. Match the storage products listed under column I with the organism given under column II, choose the appropriate option from the given options

Column I Column II

Glycogen Sargassum

Pyrenoids Nostoc

Laminarin and mannitol

Polysiphonia

Floridean starch Spirogyra

Agaricus

Codes (A) A – 3; B – 4; C – 1; D - 5 (B) A – 4; B – 3; C – 5; D – 2 (C) A – 5; B – 4; C – 1; D – 3 (D) A – 2; B – 1; C – 4; D – 3 Solution: (C) The correct matching are


Glycogen Agaricus

Pyrenoids Spirogyra

Laminarian and mannitol

Sargassum

Floridean starch Polysiphonia

15. With respect to angiosperms, identify the incorrect pair from the following

(A) Antipodal (B) Vegetative all of male gametophyte

(C) Primary endosperm nucleus (D) Cell of nucellus of ovule Solution: (A) Out of the given pairs in the option only antipodal is wrongly matched because antipodals are halploid

cells found within the mature embryo sac towards the chalazal end. Rest all three options are correctly matched. 16. The globular head of myosin contains (A) Calcium ions in large quantities (B) Troponin (C) ATPase enzyme (D) ATP Solution: (C) Globular head of myosin contains an ATPase enzyme that along with and ions catalyses the breakdown of ATP during muscle contraction. It also has binding site for ATP and active sites for actin.

17. Parbhani Kranti, a variety of bhindi (lady finger) is resistant to (A) Bacterial blight (B) Yellow mosaic virus (C) Black rot (D) Leaf curl Solution: (B) Prabhani Kranti (example of mutation breeding) is a variety of bhindi which is made resistant to yellow mosaic, virus. In this Abelmoschus esculentus was transferred from a wild species to produce this new variety. 18. Gastrula is the embryonic stage in which (A) Cleavage occurs (B) Blastocoel forms (C) Germinal layers form (D) Villi form Solution: (C) Transformation of the blastocyst into gastrula with primary germ layers by rearrangement of the cells is called gastrulation. In all the triploblastic animals three germ layers-ectoderm, mesoderm and endoderm are formed by characteristic morphogenetic movements. 19. Dense regular connective tissue is present in (A) Ligament and tendons (B) J int ap and Whart n’ J y (C) Periosteum and endosteum (D) Pericardium and heart valves Solution: (A) In dense regular connective tissue the collagen fibres are present in rows between many parallel bundles of fibres. Tendons which attach skeleton muscles to bones and ligaments which attach one bone to another are example of dense regular connective tissue. 20. Mini at it r VNTR’ ar d in (A) DNA fingerprinting (B) Polymerase Chain Reaction (PCR) (C) Gene therapy (D) Gene mapping Solution: (A) Minisatellites or Variable Number of Tandem Repeats (VNTR) are used in DNA fingerprinting technique. In VNTR, satellite DNA acts as a probe, that shows very high degree of polymorphism. 21. Note the following features and choose the ones applicable to Wuchereria bancrofti.

Coelozoic parasite Histozoic parasite

Monogenetic parasite Digenetic parasite Monomorphic, acoelomate parasite

Dimorphic, pseudocoelomate parasite (A) (B) (C)

(D) Solution: (C) Statements are correct Wuchereria bancrofti commonly called filarial worm is a digenetic, dimorphic, pseudocoelomate, histozoic and pathogenic parasite. It is digenetic because it has two stages of multiplication in two different hosts, one sexual in the mature form, the other asexual in larval stages. It is a histozoic parasite as it lives in the tissue outside of a cell body.

22. undergoes two additional process. Out of them in one process an unusual nucleotide (methyl GPT) is added to the end of molecule. What would you call this? (A) Tailing (B) Splicing (C) Termination (D) Capping Solution: (D)

The process of addition of methyl GPT at the end of is known as capping. Enzyme guanly transferase catalyses this process.

Cap is essential for the formation of -Ribosome complex. Translation is not possible if cap is lacking, because cap is identified by of ribosome unity.

23. Which type of immunoglobin ⁄ abundantly found in foetus? (A) (B) (C)

(D) Solution: (B) is the most abundant antibody in foetus as it is the only one which can cross placental barrier from mother to reach child and provides immune protection to it. 24. IUCN stands for (A) Indian Union for Conservation of Nature (B) International Union for Conservation of Nature (C) Indian Union for Chemical Nomenclature (D) International Union for Conservation of Nutrients Solution: (B) Full form of IUCN is international Union for Conservation of Nature. 25. The secretory phase in the human menstrual cycle is also called as

(A) Luteal phase and last for about days

(B) Follicular phase lasting for about days (C) Luteal phase and last for about days (D) Follicular phase and last for about days Solution: (C) The first phase of human menstrual cycle is called proliferative phase (follicular phase), while second

phase of human menstrual cycle is called as secretory phase or luteal phase and it lasts for about days. Here, the LH is secreted by anterior lobe of pituitary leading to ovulation. 26. Which one of the following statements is correct? (A) Hard outer layer of pollen is called intine (B) Sporogenous tissue is haploid

(C) Endothelium produces the microspores (D) Tapetum nourishes the developing pollen Solution: (D) Tapetum is innermost nutritive structure of anther wall which nourishes the developing pollen grain. 27. Variation in gene frequencies within population can occur by chance rather than by natural selection. This is referred to as (A) Genetic flow (B) Genetic drift (C) Random mating (D) Genetic load Solution: (B) Variation in gene frequencies within populations can occur by chance and is called as genetic drift. 28. The first stable product of fixation of atmospheric nitrogen in leguminous plant is

(A)

(B) Ammonia (C)

(D) Glutamate Solution: (B)

Nitr n

i id

ydra in

nia

The fixation of atmospheric nitrogen to ammonia is given as

→

The process in which atmospheric nitrogen gets concerted into inorganic nitrogenon (nitrate, ammonia) compounds through microorganisms is called biological nitrogen fixing.

29. If two persons with blood group marry and have sufficiently large number of children, these children could be classified as blood group. blood group blood group in ratio. Modern technique of protein electrophoresis reveals presence of both and type proteins in blood group individuals. This is an example of (A) Codominance (B) Incomplete dominance (C) Partial dominance (D) Complete dominance Solution: (A)

blood group is characterized by the presence of both antigen and i.e. and over the surface of RBCs.

Phenotype

Genotype

Antigen Antigen Here both alleles are able to express themselves forming antigens and This is called as codominance. 30. Which of the following DNA sequences qualifies to be designated as a palindrome?

(A) in one strand

(B) in one strand

(C) (D) Solution: (D) Palindromic sequence is the sequence of nucleotides whose reading is same when read from both

and direction. It is the mirror image of the sequence in its first half

31. Which one of the following pairs is not correctly matched?

(A) Vitamin- - Pernicious anaemia (B) Vitamin- - Loss of appetite (C) Vitamin- - Beri-beri

(D) Vitamin- - Pellagra Solution: (D)

Pellagra is caused by the deficiency of Vitamin (niacin), while vitamin (riboflavin) deficiency cause dermatitis. 32. Humoral immunity is mediated by (A) R-cells (B) T-cells (C) NK-cells (D) Plasma cells Solution: (D) Plasma cells plays a key role in Humoral Immunity (HMI). It activates secretion of various antibodies (B-cells) against specific antigens entering the body. 33. In the lac operon model, lactose molecules function as (A) Inducers, which bind with the operator gene (B) Repressors, which bind with the operator gene (C) Inducers, which bind with the repressor protein (D) Corepressors, which bind with repressor protein Solution: (C) Lactose or lac operon of E.coli is an example of inducible operon. Lactose is known to be the inducer

and substrate for the enzyme galactosidase. 34. Which one of the following generally acts as an antagonist to gibberellins? (A) Zeatin (B) Ethylene (C) ABA (D) IAA Solution: (C) Gibberellins and Abscisic Acid (ABA) are antagonistic to each other. Gibberllins promotes seed germination whereas ABA promotes seed dormancy. 35. The ornithine cycle removes two waste products from the blood in liver. These products are

(A) and Urea (B) Ammonia and urea

(C) and ammonia

(D) Ammonia and uric acid Solution: (B) Ornithine cycle removes both ammonia and urea from the blood. It converts ammonia into urea (in liver) and transport it to kidneys by the blood. Hence, it plays a key role in detoxification of our blood. This cycle occurs in the liver. 36. Macromolecule chitin is (A) Nitrogen containing polysaccharide (B) Phosphorous containing polysaccharide (C) Sulphur containing polysaccharide (D) Simple polysaccharide Solution: (A) Macromolecule chitin is an example complex structural hetero polysaccharide. It has nitrogen containing glucose derivatives such as N -acetyl glycosamine. It is present as the structural component of fungal cell walls and exoskeleton of arthropods etc. 37. Which of the following statement is correct in relation to the endocrine system? (A) Adenohypophysis is under direct neural regulation of the hypothalamus (B) Organs in the body like gastro-intestinal tract, heart, kidney and liver do not produce any hormones (C) Non-nutrient chemicals produced by the body in trace amount that act as inter-cellular messenger are known as hormones (D) Releasing and inhibitory hormones are produced by the pituitary gland Solution: (C) Endocrine cells are present in different parts of the gastro-intestinal tract, e.g. gastrin, secretin. GIP.

Atrial wall of our heart secretes a peptide hormone called ANF (Atrial Natriuretic Factor). ⁄ are produced by hypothalamus. Adenohypophysis is not directly under neural control, it is under the control of hypothalamic hormones, brought by portal system. 38. Following are the two statements regarding the origin of life. I. The earliest organisms that appeared on the earth were non-green and presumably an aerobes. II. The first autotrophic organisms were the chemoautotrophs that never released oxygen of the above statements which one of the following options is correct? (A) II is correct, but I is false (B) Both I and II are correct (C) Both I and II are false (D) I is correct, but II is false Solution: (B) The earliest organisms that appeared on earth were anaerobic chemoautotrophs. Chemoautotrophs were the first autotrophic organisms. They were unable to perform photolysis of water and never released oxygen, e.g. sulphur bacteria. 39. Taxonomic key is one of the taxonomic tools in the identification and classification of plants and animals. It is used in the preparation of (A) Monographs (B) Flora (C) Both Monographs and Flora (D) None of these Solution: (B)

Taxonomic keys are tools that help in identification of organisms based on the description of specific characters. e.g. flora (A resource providing information on the taxonomy, nomenclature and descriptive data of newly discovered plants). Monographs (A comprehensive treatment of a taxon). 40. Match the following columns:

Column I

Column II

Pinocytosis Euglena gracilis

Holozoic Paramecium

Parasitic Amoeba proteus

Mixotrophic Monocystis

Codes (A) A – 3; B – 2; C – 4; D - 1 (B) A – 2; B – 3; C – 4; D – 1 (C) A – 4; B – 3; C – 1; D – 2 (D) A – 1; B – 4; C – 2; D - 3 Solution: (A) The nutrition in given protozoans are as

Column I

Column II

Pinocytosis Amoeba proteus

Holozoic Paramecium

Parasitic Monocystis

Mixotrophic Euglena gracilis

41. Phellogen and phellem respectively denote (A) Cork and cork cambium (B) Cork cambium and cork (C) Secondary cortex and cork (D) Cork and secondary cortex Solution: (B) In the dicot stem the cortical cells gets differentiated to give rise to another meristematic tissue, which is called cork cambium or phellogen on the other side, It forms phellem (cork) and in the inner region it forms secondary cortical cells (phelloderm) 42. Which one of the following combinations is incorrect? (A) Rio convention - Air pollution (B) Kyoto protocol - Climate change (C) Montreal protocol - Ozone depletion (D) Ramsar convention - Wetland conservation Solution: (A) The historic, convention on biological diversity (The earth summit) held in Rio de Janerio was the Rio Convention. (in 1992) It called upon all nations to take appropriate measure for sustainable utilisation and conservation of biological diversity.

43. 'Organ of Jacobson' helps in (A) Touch (B) Vision (C) Smell (D) Hearing Solution: (C) Jacobson's organ is an axillary olfactory sense organ that is found in many animals. In mammals, the sensory neurons of Jacobson's organ detect specific chemical compounds contained within scents that are often but not always, large non-volatile molecules. It is well developed in snakes (and lizards). 44. Which one correctly describe reproduction and life cycle of fern?

(A) Spore Gamete Prothallus Sporophyte (B) Gamete Spore Prothallus Plant

(C) Prothallus Sporophyte Gamete Fern (D) Sporangia Spore Prothallus Sporophyte Plant Solution: (D) During favourable month sporangia are produced on the underside or margin of leaves in ferns. After development, it become dry and bursts to release spores. These spores germinate on the suitable substrate. Each spore absorb water, then ruptures and produce green filament which grow into prothallus (heart-shaped). Prothallus develops into young sporophyte. which in turn grows into an adult plant. 45. Monoclonal antibodies and polyclonal antibodies are produced by (A) T-memory cells (B) NK-cells (C) Plasma cells of B-lymphocytes (D) Memory cells of B-lymphocytes Solution: (C) Antibodies are produced by B-lymphocytes Monoclonal and polyclonal antibodies are particularly produced by plasma cells of B-lymphocytes when combined with myleoma cells on specific medium. These cells play a key role in specific immunological reactions. 46. All monerons (A) Contain DNA and RNA (B) Demonstrate a long circular strand of DNA, not fanned enclosed in a nuclear membrane (C) Are bacteria (D) All of the above Solution: (D) All the given statements about monerans are correct. 47. Match the following columns:


Opuntia Stem thorns

Asparagus Phylloclades

Citrus Cladodes

Codes (A) A – 1; B – 2; C - 3

(B) A – 2; B – 3; C – 1 (C) A – 3; B – 2; C – 1 (D) A – 3; B – 1; C - 3 Solution: (A)

Column I Column II

Opuntia Stem thorns

Asparagus Phylloclades

Citrus Cladodes

48. The chromosome in which centromere is situated close to one end are (A) Metacentric (B) Acrocentric (C) Telocentric (D) Sub-metacentric Solution: (B) In acrocentric chromosome, the centromere is situated close to one end of the chromosome. 49. Sliding filament theory can be best explained as (A) When myofilaments slide pass each other actin filaments shorten while myosin filament do not shorten (B) Actin myosin filaments shorten and slide pass each other (C) Actin and myosin filaments do not shorten, but rather slide pass each other (D) When myofilament slide pass each other myosin filament shorten while actin filament do not shorten Solution: (B) According sliding filament theory, during muscle contraction actin and myosin filaments shorter and slide pass each other. 50. Select the correct combination of statements regarding Myasthenia gravis

It is an auto immune disorder.

It causes insufficient acetylcholine binding that effects muscular contraction. Antibodies are developed against acetylcholine. Antibodies are developed against acetylcholine receptors.

It causes drooping of eyelids. (A) (B) (C) (D) Solution: (C)

Statements and are correct. Myasthenia gravis is an auto immune neuromuscular disease that is congenital. It leads to muscle weakness. It is caused by circulating antibodies that block acetylcholine receptors at the post-synaptic neuromuscular junction inhibiting the excitatory effects of acetylcholine and nicotic receptors at neuromuscular junctions. First noticeable symptom is weakening of eye muscle leading to drooping of eyelids. It is treated medically with acetylcholine esterase inhibitors or immuno suppressants. 51. Study the following statements and select the option with correct statements.

Pulvinus leaf base is present in some leguminous plants. In Eichhornia the petioles expand, becomes green and synthesise food.

Opposite phyllotaxy is seen in guava. (A) and (B) and (C) and (D) and Solution: (B) Most of the leaves have a swollen leaf base known as pulvinus. Its attachment on the stem is not strong. In guava opposite phyllotaxy is found. In this case all the pairs of leaves of a branch arise in same plane, so that two vertical rows are formed. In Australian Acacia. petiole gets modified into leaf like structure and synthesise food. In Eichhornia, petiole becomes spongy and helps in floating. 52. The method of directly injecting a sperm into ovum in assisted reproductive technology is called (A) GIFT (B) ZIFT (C) ICSI (D) ET Solution: (C) ICSI is intra cytoplasmic sperm injection. It is one of the techniques of Assisted Reproductive Technology (ART) that help couples to overcome their infertility. In ICSI, sperm is directly injected into ovum, in vitro to form zygote. The embryo, formed is later implanted through ZIFT into woman. 53. Appearance of antibiotic resistant bacteria is an example of (A) Adaptive radiation (B) Transduction (C) Pre-existing variation (D) Divergent evolution in the population Solution: (C) When a bacterial population encounters a particular antibiotic, those sensitive to it die. But some bacteria having mutations become resistant to antibiotics. Such resistant bacteria survive and multiply quickly as the competing bacteria have died. Soon the resistance providing genes become wide spread and entire bacterial population become resistant. Appearance of antibiotic resistant bacteria is example of pre-existing variation. 54. Post mitotic gap phase is characterised by all, except (A) Synthesis of RNA and nucleotides (B) No change in DNA content (C) Synthesis of histone proteins (D) Growth phase of the cell Solution: (C) Post mitotic gap phase is characterised by all except synthesis of histone proteins. Histone proteins are synthesised in S-phase. S-phase is called invisible phase of the cell cycle as replicated chromosomes are not visible at this stage. 55. Munch hypothesis is based on (A) Translocation of food due to Turgor Pressure (TP) gradient and imbibition force (B) Translocation of food due to Turgor Pressure (TP) gradient (C) Translocation of food due to imbition force

(D) None of the above Solution: (B) Munch hypothesis is based on the movement of phloem sap along a turgor pressure gradient. The mass flow of organic solutes takes place from the site of higher concentration, (source) to the site of lower concentration (sink). 56. Match the following columns

Column I

Column II

Molecular oxygen

ketoglutaric acid

Electron acceptor

Hydrogen acceptor

Pyruvate dehydrogenase

Cytochrome-C

Decarboxylation Acetyl Co-A

Codes (A) A – 2; B – 3; C – 4; D - 1 (B) A – 3; B – 4; C – 2; D – 1 (C) A – 2; B – 1; C – 3; D – 4 (D) A – 1; B – 3; C – 1; D - 2 Solution: (A) The correct matching

Molecular oxygen Hydrogen acceptor

Electron acceptor Cytochrome-C

Pyruvate dehydrogenase

Acetyl Co-A

Decarboxylation ketoglutaric acid

57. Roquefort cheese is ripened by using a (A) Type of yeast (B) Fungus (C) Bacterium (D) Cyanobacteria Solution: (B) 'Roquefort cheese' is a sheep milk blue cheese, which comes from the South of France. It is ripened by growing a specific fungi, i.e. Penicilliurn roqueforti which gives them a particular flavour. 58. Identify the wrong combination (A) Dryopteris Rhizome (B) Cycas Coralloid roots (C) Volvox Colonial form (D) Marchantia Pseudoelaters Solution: (D) Marchantia is a bryophyte belonging to the class-Hepaticopsida, the class of liverworts. They have elasters which are hygroscopic structures that develops inside the capsule along with spores. Elasters help in dehiscence of capsule and liberation of spores.

59. Foramen vale (A) Connects the two atria in the foetal heart (B) Is a condition in which the heart valves do not completely close (C) Is a shallow depression in the inter ventricular septum (D) Is a connection between the pulmonary trunk and the aorta in the foetus Solution: (A) Foramen ovale is an opening in the interatrial septum of the foetal heart through which both the atria communicate with each other. In adults, this aperture is closed and is represented by a small oval depression called fossa ovalis. 60. Which one of the following graphs correctly describes disruptive selection? When studying fitness level associated with body size?

(A)

(B)

(C)

(D) Solution: (D) Disruptive selection occurs when an environmental change may produce selection pressure that

favours two extreme characteristics. Selection acts on the phenotype, physical. biochemical and

behavioural traits of an organism. It indirectly adapts a population to its environment by selecting and

maintaining favourable genotypes in their give pool.

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