Science Form 3 NotesChapter 3 – Excretion (Perkumuhan)

1. Is a process in which excretory organs remove waste products from body2. Excretory organs – organs which remove waste products

Excretory Organs

Lungs Kidneys

1. CO2 1. Water 1. Water 2. Water vapour 2. Urea 2. Urea 3. Mineral salts 3. Mineral saltsImportance of Excretiona) Excretion of toxic substances – prevent us from falling sickb) Excretion of excess mineral salts – maintain body and salt contentc) Excretion of excess water - controls body temperatured) Excretion of CO2 – controls pH / acidity of blood

Skin1) Sweat glands – the actual excretory organs of the skin2) Sweat glands absorb excess of water from the blood capillaries and give it out as sweat3) Urea – breakdown product (bahan penguraian) of amino acids in the liver4) Sweating – i) cools down the body ii) controls the body temperature

The Lungs1) Cell Respiration

Glucose + Oxygen ----- CO2 + H2O + Energy ↑

2) Deoxygenated blood rich in CO2

3) Capillaries CO2 diffuses from alveoli (deoxygenated blood)4) CO2 is expelled during exhalation

The Kidneys1) Human – a pair of kidneys2) Bean shaped

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Skin (Sweat Glands)

2) Renal artery brings :i) oxygenated bloodii) excess water } iii) excess mineral salts } to be filtered and removed as ureaiv) urea }

Urea↓

Urine↓

Stored in urinary bladder↓

Released through urethra when urinary bladder is full

3) Renal vein – carries out filtered blood from kidney

The Cross Section of A Kidney

4) Functons of Kidneys1) Filter blood, remove urea, excess mineral salts and excess water2) Regulate and maintain the body’s water content3) Regulate mineral salts in blood4) Maintain the pH of blood

The Importance of Maintaining Healthy Kidneys1) Kidneys can be damaged byi) Hypertensionii) Diabetesiii) Physical Injuriesiv) Excessive use of alcohol

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2) Kidney failure can be treated through dialysis3) Dialysis machine – “artificial kidney”4) A person has to undergo 3 or 4 times a week for several hours

A Dialysis Machine

Excretion in Plants1) Waste products are a) CO2 b) H2O c) Mineral Salts d) Nitrogenous Waste

2) Some excretory products are stored ina) leaves b) fruit c) bark d) vacuoles

3) Some waste products are usefula) latex - gloves, tyresb) resin - gum, paintc) quinine - medicine for malaria

4) Some waste products are harmfula) opium - addictive – poppy fruitb) cocaine – addictive – coffee beansc) nicotine – addictive – tobacco leaves

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Science Form 3 NotesChapter 4 – Reproduction

1) Reproduction – a process in which new individuals or offsprings (anak) are produced2) Importance – to ensure the survival of species (kemandiran spesies)

Reproduction

sexual

a. Formation of new individuals a. Formation of new individuals with without gametes gametesb. One parent is involved b. Two parents are involvedc. Does not requires gametes c. Requires gametesd. Have the same characteristics d. Characteristics are inherited (diwarisi) as the parents from both parents

Fertilisation1) Fusion (percantuman) of male gametes (sperm) and female gametes (ovum)2) Gamete – reproductive cell (sel pembiakan)

Fertilisation

Internal Fertilisation External Fertilisation

a. Gametes are fertilized inside a. Gametes are fertilized outside the female’s body the female’s bodyb. Zygote develops inside the b. Zygote develops outside the female’s body female’s bodyc. Very few eggs/ovum are produced as the c. Many eggs/ovum are produced as the chance for fertilization is high chance for fertilization is lowd. Ex – humans, mammals, birds, reptiles This is because :- reptiles, insects i) the eggs or sperms may be eaten by predators ii) the eggs or sperms may be carried away by water d. Ex - fish, amphibian

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asexual

Asexual Reproduction5 typesa) Binary Fussion (Belahan Dedua)b) Budding (Pertunasan)c) Spore Formation (Pembentukan Spora)d) Regeneration (Penjanaan Semula)e) Vegetative Reproduction

A Binary Fussion

Parent cell begins to divide two new identical organisms are formed

1) Mature parent cell divides into two to form 2 new organisms2) Ex – amoeba, paramecium, euglena, bacteria

B Budding

1) Parent produces a bud2) Bud grows and separates from parent3) Ex – hydra (tumbuhan air), yeast (ibu roti)

C. Spore Formation

1) Sporangium ruptures and mature spores are released2) Mature spores will form new organisms when condition is suitable3) Ex – fern, moss, mushroom, mucor (bread)

D. Regeneration1). Each part forms a new individual

2) Each piece of the parent that is separated will grow into a new individual3) Ex – planaria , starfish

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E. Vegetative Reproduction1) Certain parts of plants can grow into a new plant2) These parts area) leaves b) shoot c) root3) Vegetative reproduction – reproduction of new plants using any part of plant except seeds

A. Leaves1) These plants have leaves that produce buds2) These buds can grow into new plants when the leaves are detached from the parent plant3) Ex – Byrophilum, Begonia

B. Roots1) These plants have roots that store food2) Ex – sweet potatoes, tapioca

C. Stem1) Have modified stem that produces bud. They area) runners b) rhizomes c) tuber d) corm e) sucker f) bulb

A) Runners/Stolom1) Stem that grow horizontally (mendatar) over the surface of the ground2) Shoots and the roots of the young plants grow from the nodes of the runner3) When the interneed dies, the young plant becomes independent

Ex – strawberry plant, carpet grass

B) Rhizomes 1) Horizontal, underground storage stem which has buds 2) Ex – ginger, lallang, asparagus

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C) Suckers1) New shoots which grow from the underground part of stem2) The sucker grows upwards and becomes new plant3) Ex – banana, pineapple

D) Tubers1) A swollen underground stem with leaves and buds2) The buds grow into shoots which produce leaves and roots3) Ex – potatoes, dahlia

E) Corms1) A thick shoot and swollen underground2) Leaves and buds are found on the corm3) Ex – garlic, onions

Advantages of Vegetative Reproduction1) Grow taller than seed2) Obtain food from the parent until they can make their own food3) Good characteristics of parent plants are passed to new plants4) Does not require agents of pollination (water, air, insects and wind)5) Does not need fertilization

Disadvantages of Vegetative Reproduction1) Have less variety 2) Bad qualities of the parent plant are passed to new plants3) New plants grow in the same area as the parent plant so there is competition (persaingan) for space, nutrients and sunlight

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Plant/Tissue Culture

Part of root, stem, leaf, bud or shoot of a plant can be used for tissue culture

Applications DescriptionsPropagation of Plants Plants tissue culture is useful in the

cultivation of plant like orchids or ornament plants (tumbuhan perhiasan)

Production of pest- resistant and disease- resistant plant

Plant tissue culture is used to produce plants that are tolerant to pests and diseases

Cloning An unlimited number of plants that are genetically similar can be produced by tissue culture within a short period of time

The Male Reproductive System

Part FunctionScrotum 1) Protects testis

2) Holds testis outside the body to keep coolTestis 1) Produce sperms

2) Produce male hormones(testesterone)Sperm Vesicle 1) Stores sperm from testes Prostate Gland 1) Produces fluid that nourishes sperms

Semen = Sperm + Fluid PG + Fluid SVUrethra 1) Carries sperm to the outside of the body

2) Transports urinePenis 1) Transfers sperms into a female’s bodySeminal Vesicle 1) Stores sperm temporarily

2) Produces fluid that nourishes (menyuburkan) sperms

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Sperm1) Smallest cell in the body2) Mobile (boleh bergerak)

The Structure of A Sperm

Front View Side View

Changes In A Male During Puberty1) Puberty - sexual organs start to produce sex productive cells - accompanied by a) physical changes b) physiological change c) emotional change2) Physical changes in a male during pubertya) Shoulders widen and chest becomes broaderb) Body height and weight increases rapidlyc) An increase in the size of testes and penisd) The testes start to produce gametes sex reproductive cellse) Body becomes more muscular in the upper bodyf) Growth of hair on the face (moustache and beard) the chest, the armpits and around the pubic region

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Changes In A Female During Puberty1) The female’s sex hormones cause physical, physiological and emotional changes in a female2) The ovary begins to release a mature egg or ovum and continues to release an egg every 28 days

The Female Reproductive System

Parts FunctionOvary 1) Produce egg cells or ovum

2) Produce female hormonesFallopian Tube 1) Connects ovaries to uterus

2) A place where fertilization takes place3) Carry ovum to uterus

Uterus 1) Implantation occurs2) Protects embryo and foetus during pregnancy

Cervix 1) Secretes (merembeskan) mucus to protect against bacterial infection2) Serves as birth canal (salur)

Vagina 1) Receives sperms2) Serves as birth canal

Nucleus (contain genetic information of female parent) Jelly coat Cytoplasm Cell membrane

The Structure of an Ovum

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The Role of an Ovum in Reproduction1) The ovum is the largest cell in the human body2) It has a nucleus which carries the genetic material of the female parent to be passed down to the offspring3) The role of the ovum is to be fertilized by a sperm to form a zygote

Human Ovum1) Largest cell in the body2) Female reproductive cell3) Cannot move freely4) Sphere in shape5) Can live about 24 – 48 hours

The Menstrual Cycle

1) Menstrual cycle – The first day of a menstruation to the first day of the next menstruation2) 1 menstrual cycle – normally takes about 28 days3) Menstrual – monthly periodic discharge of a) blood } b) mucus } c) cells of uterus lining } which come out through/ from the vagina d) unfertilized ovum }

4) Menstruation - lasts 5 – 7 days - occurs once in every 28 days5) Menstruation - starts when a girl reaches puberty - stops at about the age of 50 years (menopause)6) Ovulation - release of an ovum by the ovary7) Menstrual cycle has 4 phase a) menstruation phase b) repair phase c) fertile phase d) pre-menstruation phase

copyright@mmk2010A. Menstruation Phase

1) Day 1 – Day 72) Menstruation occurs3) The lining of the uterus wall breaks downB. Repair phase1) Day 7 – Day 112) The lining begins to thicken3) More blood vessels are formed4) Preparation to receive any ovum that is fertilizedC. Fertile Phase1) Day 11 – Day 172) Ovulation usually happens on the 14th day3) Fertile phase – chances of fertilizing an ovum during this period is very high

Fertile Phase

Ovum NOT Fertilised Ovum Fertiliseda) Pre- menstrual phase takes place a) Pregnancy startsb) Tissues and blood vessels on the b) Tissues and blood vessels do uterus lining break away not break awayc) Mensus is discharge c) Zygote moves into uterus i) blood ii) mucus iii) unfertilized ovum iv) lining of the uterus wall d) Implantation occurs e) Ovulation and menstrual cycle stopsD. Pre- Mentrual Cycle1) Day 17 – Day 282) The lining of uterus wall continues to thicken3) If fertilization has occurred zygote embryo4) If fertilization did not occur, the ovum will disintegrate (terurai)

Fertilisation and Pregnancy1) Fertilisation – fusion between sperm and ovum takes places in the fallopian tube

Sperms surround the ovum Only the head of ONE sperm The nucleus of the gets into the egg cell sperm and the nucleus of the ovum fuse to form a zygote

copyright@mmk20102) Ovulation – release of an ovum on the 14th day (13th – 15th days)

3) Sperms swim through cervix, uterus to reach the fallopian tube4) Sperms meet the ovum in the fallopian tube5) Only one sperm fuses with the ovum6) The zygote moves along the fallopian tube towards the uterus

7) During the passage to uterus, the zygote divides again and again to form a ball of cells called embryo 8) The embryo attaches itself on the wall of the uterus by the structure called placenta9) The placenta is connected to the embryo by the umbilical cord10) After implantation, a membrane develops to enclose the embryo in a double layered capsule called amniotic cavity11) The amniotic cavity is filled with a fluid called amniotic fluid12) The fluid has two function a) acts as a shock absorber (penyerap renjatan) and protects the embryo b) buoys up (mengapungkan) the embryo so that it can move more freely during its development13) Function of Placenta a) transfers nutrients, antibodies, oxygen from the mother’s blood into that of the embryo b) transfers metabolic waste products (CO2 and Urea) from the embryo’s blood into the mother’s blood14) Function of Umbilical Cord a) Transfers dissolved (terlarut) nutrients, antibodies and oxygen from the placenta to the embryo b) Transfers metabolic waste products from the embryo to the placenta15) The mother’s blood system and the embryo’s blood system are separate system16) Dissolved nutrients, hormones, antibodies, oxygen

Diffuse into

The placenta

The umbilical cord

Blood capillaries of embryo(vice versa)

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17) Geostation period to birth - period from fertilization - about 38 weeks – 40 weeks18) After birth it is called a baby19) During birth (a) uterus wall contracts the membranes surrounding the foetus (b) cervix opens because of the pushing force from the i) mother ii) force of contraction of the uterus wall push the baby through the vagina (c) umbilical cord is tied in two places (to prevent bleeding)

20) The placenta, umbilical cord and ruptured membrane which are discharged is called the after birth

Prenatal Care1) Prenatal care is the care taken by a pregnant woman to ensure the healthy growth and development of the foetus 2) Taking nutritious food is a must. They are :-a) Protein – required by foetus to build body tissues and growth eg. fish, milk, meat, eggsb) Carbohydrates and fats – required to supply energy to the foetus eg bread, rice and potatoesc) Mineral salts – essential for good health. Eg- calcium is required for the formation of bones and iron is for the formation of haemoglobind) Vitamins – builds expectant mother’s (ibu mengandung) resistance against diseases (rintangan terhadap penyakit). Eg. Vitamin D – formation of strong bones

The Importance of Avoiding Harmful SubstancesA. Smoking1) Nicotine - slows down the growth of foetus - rapidly stimulates the heart of foetus - can cause premature birthB. Alcohol- damage brain cells of foetus- slows down the birth of foetusC. Other drugs- causes deformity in foetus

The Importance of Research In Human Reproduction

Sterility (Kemandulan) and Ways to Overcome Sterility

Birth Control

Hormone Treatment1) Used to increase sperm and egg production

Surgery1) Used to correct blocked fallopian tube

In Vitro Fertilisation (IVF)1) Eggs from human are mixed with sperms in culture dishes

1) Rhythm Method - Refraining from copulation during the menstrual cycle2) Condoms - Prevents sperms from being transferred into vagina3) Intrauterine Contraceptive Devise (IUCD) - Small plastic or metal object that is normally inserted by a doctor into the uterus to prevent implantation4) Spermicides - contains chemicals that will kill the sperm5) Birth Control Pills - prevent ovulation and prevent the release of ova - made of artificial hormones6) Surgical Method (a) Vasectomy – sperm ducts are cut to prevent sperms from entering the urethra (b) Ligation – fallopian tubes are cut and tied to prevent eggs from reaching the uterus

The Reproductive System In Flowering Plants

1) Flower – has reproductive organs of flowering plants2) Functions of a flower – to produce fruit with seeds

Flower parts FunctionPedicel (batang) 1) Supports the flower

2) Holds the flower in a prominent positionSepal 1) Protects the other parts of flower in bud stagePetals (ranggi) 1) Attracts insects and birds for pollination

2) Protect the other parts of flowers during bud stageNectary (Kilang Nektar)

1) Produces sugary liquid called nectar2) Attracts insects for pollination

Stamen 1) Male reproductive organ2) Consists of a) Anther – produces pollengrains (debunga) b) Filament –

i) Supports the anther ii) holds it in a prominent position (kedudukan yang baik)

Pistil 1) Female reproductive organ2) Consists of a) Stigma – receives pollengrain b) Style – support the stigma c) Ovary – produces ovules d) Ovules – contain female gametes

Types of Flowers

Type

The Reproductive Part of Flower – Stamen

Anther Pollengrains

Filament Anther

FilamentPistil

Stigma (sticky surface to enable pollen grains to stick) Style Ovary Ovule (female gamete)

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Pollination

Unisexual Flower1) Flowers that are either male or female flower2) Male flowers contain stamen3) Female flowers contain pistil4) Ex. Papaya, Maize

Bisexual Flower1) Conain both stamen and pistil2) Ex. Hibiscus, morning Glory

1) Transfer of pollengrains from anther to stigma

Types of Pollination

Comparision between self- pollination and cross- pollination1) Similarity involves transfer of pollengrains from anther to stigma2) Differences : -

Self Pollination Cross Pollination1 Number of Plant Involved 2 or more

Does not produce new variety

Variety of Offspring Produces new variety

Posesses characteristics of only one plant

Characteristics Posesses characteristics of both parent plant

Offspring is NOT resistant to diseases

Resistance to diseases Offspring is more resistant to diseases

Offspring cannot adapt (menyesuaikan diri) to environment change

Adaptation to Environment Offspring can adapt to environmental changes

Advantage of Cross Pollination1) Allows combination of characteristics of both parent cell2) Produce plants with good characteristics such as :- i) produce seeds of better quality ii) more resistant to diseases iii) can survive when environment change iv) produces fruit of better quality

copyright@mmk2010Agent of Pollination and Characteristics of Flowers

Self Pollination- Transference of pollen grainsa) from anther to stigma of the same flowerb) from anther to stigma of different flower from the same plant

Cross Pollination- Transference of pollen grainsa) from one plant to another plant

1) Pollination is carried out by several agents namelya) windb) waterc) insectsd) birds, animals, humans

2) Pollination by animals a) bats - white/ browny flowers - strong scent (haruman) flowers b) birds - brightly coloured flowers - produces a lot of nectar

3) Pollination by insects a) butterflies/bees b) pollengrains are rubbed on insects body and legs when it sucks nectar c) these pollen grains are transferred to other flowers when these insects visit other flowers

4) Pollination by water a) Aquatic plants b) plants produce pollen grains which floats on the surface of water and carry to other flowers

5) Pollination by Wind a) Wind blows pollen grains far from parent plant

6) Comparison between insect- pollinated and wind- pollinated flowers

Features Insect- Pollinated Flowers Wind-Pollinated FlowersSize Big Small

Colour Brightly coloured White or DullNectar Produces nectar Does not produces nectarSmell Scented Not scented

Pedical Short LongAnther Small Big

Filament Short Long; hangs out of flowerPollen grains Small amount, big, sticky, rough Plentiful,small, light, smooth

Stigma Short, sticky Long, feathery, exposed to the windStyle Short Long

Example Sunflower, Flame of the forest (Bunga Semarak Api)

Lallang

copyright@mmk2010The Development of Fruits and Seed in Plants

1) Pollination is followed by fertilisation2) Fertilisation- fussion of a male gamete and a female gamete

Steps During Fertilisation

Pollen grains lands on Stigma(stigma produces sticky and sugary fluid)

Pollen grains absorps the sugary liquid and increase in size

Pollen grain grows a pollen tube that grows in the style

Each pollen grain has 2 male gametes which reaches the ovule

Fertilisation- occurs when one of the male gametes fuse with the female gametes- zygote is found and develops into an embryo

After fertilization- ovary develops into fruit- ovule develops into seed- sepals petals and stamen, style, stigma will wither (layu) and fall off

after fertilisation

* stamen ------- anther --------pollengrains---------male gametes fuse together pistil---------- ovary ---------ovules --------------- female gametes fertilization

flowers-------new parts --------embryo--------zygote

copyright@mmk2010Germination of Seeds

1. There are two types of seeds (a) monocotyledon - one cotyledon (b) dicotyledon - two cotyledon