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22 Reproduction • 22.1 What is reproduction? • 22.2 Asexual reproduction in bacteria (Extension) • 22.3 Asexual reproduction in flowering plants (Extension) • 22.4 Sexual reproduction in flowering plants (Extension) • 22.5 Fruits and seeds (Extension) 22 Reproduction • 22.6 The advantages and disadvantages of sexual reproduction compared with asexual reproduction in flowering plants (Extension) • 22.7 Sexual reproduction in humans • 22.8 Human embryos • 22.9 The birth process • 22.10 Parental care • 22.11 Birth control • Mind Map 22.1 What is reproduction? What is 22.1 What is reproduction? a process that living organisms can produce new offspring to replace those members that die 22.1 What is reproduction? Reproduction Asexual reproduction Sexual reproduction 22.1 What is reproduction? is the production of offspring from a single parent without the fusion of gametes 22.1 What is reproduction? is the production of offspring from the fusion of gametes 22.1 What is reproduction? Asexual Reproduction Sexual Reproduction Number of parents involved One Two Involvement of gametes No Yes Cell division involved Mitosis Meiosis Does fertilisation occur? No Yes Genetic make-up of the offspring Identical to parent Different from parents 22.2 Asexual reproduction in bacteria in bacteria 22.2 Asexual reproduction in bacteria Bacteria undergo binary fission to form two identical daughter cells 22.3 Asexual reproduction in flowering plants in flowering plants 22.3 Asexual reproduction in flowering plants 1 2 3 4 5 22.3 Asexual reproduction in flowering plants Bud germinates Vegetative propagating organ Bud Storage organ provides food for the growth of new shoots Adventitious roots are formed to absorb water 1 2 22.3 Asexual reproduction in flowering plants Green leaves develop Vegetative propagating organ Bud Carry out photosynthesis Storage organ dries up as food is being used up 1 2 3 22.3 Asexual reproduction in flowering plants Photosynthetic product is stored in a new storage organ Vegetative propagating organ Bud A new storage organ 1 2 3 4 22.3 Asexual reproduction in flowering plants the storage organ remains dormant until next year A bud is formed for next growing season Vegetative propagating organ Bud 1 2 3 4 5 22.3 Asexual reproduction in flowering plants Many flowering plants can reproduce asexually by this method Vegetative propagating organ Bud vegetative propagation 22.3 Asexual reproduction in flowering plants bulbs Also called perennating organs Vegetative propagating organ Bud corms rhizomes tubers 22.3 Asexual reproduction in flowering plants Bulbs Stores food fleshy leaf An onion bulb bud Provides food for the germination of bud 22.3 Asexual reproduction in flowering plants Corms Provides food for the germination of bud bud corm Stores food A Gladiolus corm 22.3 Asexual reproduction in flowering plants Rhizomes bud rhizome Stores food Provides food for the germination of bud A lotus rhizome 22.3 Asexual reproduction in flowering plants Tubers bud tuber Stores food Potato tubers Provides food for the germination of bud 22.3 Asexual reproduction in flowering plants Perennating organ Origin of organ Region of food storage Examples Bulb Stem Fleshy scale leaves Onion, daffodil Corm Stem Swollen stem base Gladiolus, Crocus Rhizome Stem Entire length of horizontal stem Ginger, lotus, iris Stem Tip of side branch of stem Potato, arrowhead Tuber 22.3 Asexual reproduction in flowering plants Experiment 22.1 To cultivate any vegetative propagating organ of flowering plants 1. Choose a vegetative propagating organ of flowering plants, such as tuber, bulb, rhizome or corm. 2. Put the vegetative propagating organ on a pot of soil (sandy soil is more suitable) and cover it with soil of 2 cm thickness. 3. Water it once or twice a day. 4. Observe its change during growth. 22.3 Asexual reproduction in flowering plants Experiment 22.2 To examine one vegetative propagating organ 1. Choose one vegetative propagating organ which is beginning to sprout into a new plant. 2. Observe it carefully and identify the parts in vegetative propagation. 22.3 Asexual reproduction in flowering plants Advantages of vegetative propagation 1 As large food reserves are provided for daughter plants It is a rapid way of reproduction 22.3 Asexual reproduction in flowering plants Advantages of vegetative propagation 2 Offspring are genetically identical to parent Desirable characters can be retained 22.3 Asexual reproduction in flowering plants Advantages of vegetative propagation 3 No external agents are required It is a surer way of reproduction 22.3 Asexual reproduction in flowering plants Disadvantages of vegetative propagation 1 Overcrowding may occur It leads to competition for the same resources among the offspring 22.3 Asexual reproduction in flowering plants Disadvantages of vegetative propagation 2 No genetic variation occurs in offspring This decreases the ability of offspring to adapt to changes in the surroundings 22.3 Asexual reproduction in flowering plants Disadvantages of vegetative propagation 3 The parent plant and the daughter plants are linked together Diseases of the parent plant are rapidly transmitted to the offspring 22.3 Asexual reproduction in flowering plants Advantages Disadvantages Rapid way of reproduction Competition among offspring Desirable characters can be retained Less ability to adapt to changes Surer way of reproduction Disease transmission 22.4 Sexual reproduction in flowering plants in flowering plants 22.4 Sexual reproduction in flowering plants The sex organ in flowering plant is 22.4 Sexual reproduction in flowering plants Structure and functions of a flower 3 a a b b c d 2 1 5 4 22.4 Sexual reproduction in flowering plants Structure and functions of a flower 2. The sepals of most flowers are green for photosynthesis 1. Protects the flower buds sepal 1 22.4 Sexual reproduction in flowering plants Structure and functions of a flower 1. Brightly coloured to attract insects 2 petal 2. Has insect-guides which guide insects to the base of the petals to get nectar from nectary 22.4 Sexual reproduction in flowering plants Structure and functions of a flower Secretes nectar for insects to feed on nectary 5 22.4 Sexual reproduction in flowering plants Structure and functions of a flower stamen 3 a anther filament b Produces pollen grains Supports anther 22.4 Sexual reproduction in flowering plants Structure and functions of a flower 3 a a b b c d 2 1 5 4 22.4 Sexual reproduction in flowering plants Structure and functions of a flower a stigma style b carpel 4 c ovary ovule d 22.4 Sexual reproduction in flowering plants Structure and functions of a flower Receives pollen grains stigma Allows pollen tube to grow through style carpel ovary ovule Contains ova Contains ovules 22.4 Sexual reproduction in flowering plants Experiment 22.3 Examination of flowers 1. Obtain a flower, such as Bauhinia, Gladiolus, Lily or Cassia. 2. Identify the floral parts. How many sepals, petals, stamens and carpels are there? Use a table to record these floral parts. 3. Use a scalpel to cut open the carpel longitudinally. Can you see any ovules? You can use a hand lens to make your observation. 4. State the functions of the floral parts. 22.4 Sexual reproduction in flowering plants Pollination pollen grain 22.4 Sexual reproduction in flowering plants Pollination 22.4 Sexual reproduction in flowering plants Pollination is the transfer of pollen grains from the anther to the stigma 22.4 Sexual reproduction in flowering plants Pollination produces pollen sac anther pollen grains carry male gametes when anther is mature it splits open 22.4 Sexual reproduction in flowering plants Pollination ovary 22.4 Sexual reproduction in flowering plants Pollination ovule contains ovum 22.4 Sexual reproduction in flowering plants Pollination Insect pollination Wind pollination 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Larger Size Wind-pollinated flower Smaller 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Petal Colour Brightly-coloured Wind-pollinated flower Dull-coloured 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Present Scent Wind-pollinated flower Absent 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Present Nectary Wind-pollinated flower Absent 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Anther Enclosed within flower, to brush pollen grains onto insect body Wind-pollinated flower Hanging out of flower, for catching the wind 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Stigma Enclosed within flower, to brush the insect body to get pollen grains on it Wind-pollinated flower Large and feathery, exposed, for catching pollen 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Pollen grains Produced in small number Wind-pollinated flower Produced in large number Lighter, with smooth surfaces Rougher, heavier with spikes for sticking to insects 22.4 Sexual reproduction in flowering plants Insect-pollinated flower Occurrence Appear in warmer seasons, when there are more active insects Wind-pollinated flower In windy area Sometimes appear in colder and drier seasons 22.4 Sexual reproduction in flowering plants Insect-pollinated flowers Wind-pollinated flower Size Large Small Petals Brightly coloured Dull coloured Nectary Present & produces nectar Absent Scent Strongly scented No scent Inside the flower Hanging out of the flower Anthers 22.4 Sexual reproduction in flowering plants Stigma Insect-pollinated flowers Wind-pollinated flower Inside the flower Large, feathery, exposed Rougher, heavier with spikes Lighter with smooth surfaces Produced in small numbers Produced in large numbers In warmer seasons In colder & drier seasons Pollen grains Occurrence 22.4 Sexual reproduction in flowering plants Experiment 22.4 To examine the adaptive features of insect-pollinated and windpollinated flowers 1. Your teacher will give you some insect-pollinated flowers and some wind-pollinated flowers. Which is which? How do you know? 2. With the aid of a hand lens, examine each flower carefully. Which features does it have? 22.4 Sexual reproduction in flowering plants Pollination Selfpollination Crosspollination 22.4 Sexual reproduction in flowering plants Self-pollination Same flower Different flower on the same plant Flower A Flower B 22.4 Sexual reproduction in flowering plants Self-pollination Transfer of pollen from the anther to the stigma of the 1. SAME flower, or 2. another flower on the SAME plant 22.4 Sexual reproduction in flowering plants Same species Plant A Flower A Cross-pollination Plant B Flower B 22.4 Sexual reproduction in flowering plants Cross-pollination Transfer of pollen to a flower of DIFFERENT plant of the SAME species 22.4 Sexual reproduction in flowering plants Fertilisation Male gamete fuses with the egg cell (ovum) to form a zygote 22.4 Sexual reproduction in flowering plants Fertilisation 1. Stigma cells secrete a sugary solution Pollen grain sticks to the stigma 22.4 Sexual reproduction in flowering plants Fertilisation Pollen tube 2. Sugary solution stimulates the pollen grain to develop a pollen tube 22.4 Sexual reproduction in flowering plants 3. Pollen tube secretes enzyme to digest cells Pollen tube grows down the style and the ovary Fertilisation Pollen tube 22.4 Sexual reproduction in flowering plants 3. Pollen tube secretes enzyme to digest cells Fertilisation Male gamete Pollen tube Pollen tube grows down the style and the ovary Carrying male gametes towards the micropyle of the ovule Micropyle 22.4 Sexual reproduction in flowering plants 3. Pollen tube secretes enzyme to digest cells Fertilisation Pollen tube Pollen tube grows down the style and the ovary Carrying male gametes towards the micropyle of the ovule Micropyle 22.4 Sexual reproduction in flowering plants Fertilisation 4. Male gamete is liberated into the ovule Pollen tube Fuses with ovum Fertilisation Ovum Micropyle 22.4 Sexual reproduction in flowering plants Fertilisation 4. Male gamete is liberated into the ovule Pollen tube Fuses with ovum Fertilisation Ovum Micropyle 22.5 Fruits and seeds & 22.5 Fruits and seeds Ovary Fruit ovary wall fruit wall ovule seed sepals petals stamens stigma style wither and fall off 22.5 Fruits and seeds Dispersal of seeds by fruits is a process that seeds spread from the parental plant 1 2 To prevent overcrowding and reduce competition Allows plants to colonise new areas 22.5 Fruits and seeds Dispersal of seeds by fruits Methods By animals By wind By explosion By water 22.5 Fruits and seeds By animals 1 Hooks cling to animals’ fur 3 2 Seeds are surrounded by hard seed coat resist to animals’ digestive enzymes Some are fleshy fruits provide food to animals 22.5 Fruits and seeds By wind Hair Wing Light & large surface area allow dispersal over a great distance 22.5 Fruits and seeds By explosion 1 When the skin dries out 2 The seeds are 3 The seeds are scattered over a wide area suddenly released as the pod splits open 22.5 Fruits and seeds By water 1 Some fruits e.g. coconut 2 3 Contains air space which makes the fruit buoyant 22.5 Fruits and seeds Structure of dicot seeds External appearance Longitudinal section 22.5 Fruits and seeds Structure of dicot seeds seed coat cotyledon plumule radicle micropyle embryo 22.5 Fruits and seeds Structure of dicot seeds seed coat cotyledon plumule radicle micropyle A tough, protective covering 22.5 Fruits and seeds Structure of dicot seeds seed coat Stores food cotyledon plumule Grows into the leafy shoot radicle micropyle Grows into the root 22.5 Fruits and seeds Structure of dicot seeds seed coat cotyledon plumule radicle micropyle Allows water to enter before germination 22.6 The advantages and disadvantages of sexual reproduction compared with asexual reproduction in flowering plants Sexual Asexual 22.6 The advantages and disadvantages of sexual reproduction compared with asexual reproduction in flowering plants Advantage Fast – one individual can produce a large number of offspring Disadvantage All offspring are identical, less genetic variation Overcrowding may occur Asexual Reproduction Only vegetative organs are required Diseases may be transmitted from parent plants to the offspring 22.6 The advantages and disadvantages of sexual reproduction compared with asexual reproduction in flowering plants Sexual Reproduction Advantage Disadvantage Genetic variation occurs, offspring have a greater chance to adapt to changes in environment Slow More complicated – two parents are required Overcrowding can be avoided Sex organs are involved for mating Diseases are not easily transmitted to the offspring required fertilisation of male and female gametes 22.7 Sexual reproduction in humans in humans male female 22.7 Sexual reproduction in humans Males Produces sperms & male sex hormones epididymis testis scrotum 22.7 Sexual reproduction in humans Males Storage of sperms epididymis testis scrotum 22.7 Sexual reproduction in humans Males sperm duct transports sperms epididymis testis scrotum 22.7 Sexual reproduction in humans Males seminal vesicle prostate gland Cowper’s gland secrete seminal fluid 22.7 Sexual reproduction in humans Males Activates & nourishes the sperms Neutralises the acidity of vagina seminal vesicle prostate gland Cowper’s gland secrete seminal fluid 22.7 Sexual reproduction in humans Males seminal vesicles testes prostate glands secrete Cowper’s glands secrete seminal fluid sperms semen 22.7 Sexual reproduction in humans Males 22.7 Sexual reproduction in humans Males Joins the sperm ducts to transport sperms urethra penis For copulation 22.7 Sexual reproduction in humans in humans male female 22.7 Sexual reproduction in humans Females ovary Produces ova and female sex hormones 22.7 Sexual reproduction in humans Females oviduct 1. Possesses a ciliated lining and a muscular wall helps to move the ova 2. Site for fertilisation 22.7 Sexual reproduction in humans Females 1. Protects the developing embryo uterus 2. Provides a constant internal environment for the embryo to develop 3. Contracts rhythmically and powerfully to expel the foetus out at birth 22.7 Sexual reproduction in humans Females 1. Receives the penis during copulation vagina 2. Acts as a birth canal for the foetus 22.7 Sexual reproduction in humans Experiment 22.5 To examine the male and female reproductive systems of dissected mammals of a human torso 1. You will be given a dissected female rat so as to show the reproductive system. Examine it carefully. Try to identify the ovaries, the oviducts and the uterus. coiled oviduct uterus ovary 22.7 Sexual reproduction in humans Experiment 22.5 To examine the male and female reproductive systems of dissected mammals of a human torso 2. You will be given a dissected male rat to show the reproductive system. Examine it carefully. Try to identify the penis, scrotum and sperm duct. 22.7 Sexual reproduction in humans The structure of 22.7 Sexual reproduction in humans Structure of sperm For movement Contains genetic materials head middle piece tail Contains mitochondria which supply energy 22.7 Sexual reproduction in humans Structure of ovum Nucleus Contains genetic materials cytoplasm Contains yolk which nourishes the egg and the developing embryo 22.7 Sexual reproduction in humans Structure of ovum For protection Plasma membrane Jelly coat Follicle cell 22.7 Sexual reproduction in humans Sperm Ovum Size Smaller Larger Shape Tadpole-like, with a head and a tail Spherical Movement Can swim using a tail Cannot move by itself No food reserve Has good reserve (yolk) Millions produced Much fewer made Food reserve Number produced 22.7 Sexual reproduction in humans 22.7 Sexual reproduction in humans Remaining part yellow body A section through a human ovary Ovum surrounded by follicle cells follicle ovum to oviduct Ovum is released into the oviduct ovulation Ovum is developing inside the follicle When the ovum is mature, the follicle bursts 22.7 Sexual reproduction in humans 22.7 Sexual reproduction in humans During puberty Male Female Testes grow & produce sperms Ovaries grow & release eggs Secondary sexual characteristics are developed Secondary sexual characteristics are developed 22.7 Sexual reproduction in humans Male Secondary sexual characteristics 1 Growth of pubic hair and hair on face and in armpits 2 3 Deepening of voice & enlargement of larynx Muscle development 4 Widening of shoulders 22.7 Sexual reproduction in humans Female Secondary sexual characteristics 1 Growth of pubic hair 2 3 Growth and development of breasts Widening of hips 4 More fat deposits under skin 22.7 Sexual reproduction in humans Sex hormones Male sex hormone testosterone Female sex hormones oestrogen Male Female secondary sexual characteristics secondary sexual characteristics 22.7 Sexual reproduction in humans 22.7 Sexual reproduction in humans Menstrual Cycle From day 1 – day 5 Uterine lining breaks down & passes out with the unfertilised ovum Menstrual flow This period is called menstruation 22.7 Sexual reproduction in humans Menstrual Cycle From day 5 – day 14 The uterine lining builds up again which is induced by female sex hormone 22.7 Sexual reproduction in humans Menstrual Cycle Day 14 Ovulation occurs 22.7 Sexual reproduction in humans Menstrual Cycle From day 14 – day 28 The uterine lining remains thick and spongy Thickened uterine lining is ready to receive a fertilised ovum 22.7 Sexual reproduction in humans Menstrual Cycle Ovary From day 1 – day 13 After ovulation Day 14 Follicle is developing until mature Yellow body is developed Ovulation 22.7 Sexual reproduction in humans Summary Follicle starts to develop Follicle is developing until mature Yellow body is developed Thickness of uterine lining Menstruation * Uterine lining remains thick 14 ovulation 15 - 28 Uterine lining is developing 1-5 6 - 13 Follicle starts to develop again Menstruation starts again Day 22.7 Sexual reproduction in humans & 22.7 Sexual reproduction in humans Sexual intercourse When a male is sexually excited Blood is pumped into the spaces inside the penis Penis becomes erect and hard Erect penis is inserted into vagina of female 22.7 Sexual reproduction in humans The sperm meets the ovum in oviduct The sperms swim through uterus & into oviduct The semen is squeezed into vagina semen Ejaculation 22.7 Sexual reproduction in humans Fertilisation The head of sperm secretes enzyme which dissolves the jelly coat Only the head can penetrate into & fuse with the egg The protective membrane becomes impenetrable to other sperms 22.7 Sexual reproduction in humans Fusion of gametes Forms a zygote fertilised Egg 22.7 Sexual reproduction in humans Twins Identical Non-identical 22.7 Sexual reproduction in humans Identical twins After fertilisation, ONE zygote is formed It divides into two cells by mitosis Each cell develops separately into a normal embryo Twins are of the same sex & are genetically identical 22.7 Sexual reproduction in humans Non-identical twins Two eggs are shed from the ovary & fertilised TWO zygotes are formed Twins may have different sexes; They are genetically different 22.8 Human embryos 22.8 Human embryos 4. An embryo is formed 3. Zygote divides successively by mitosis 2. Fertilisation occurs in oviduct and a zygote is formed 5. Embryo embedded in the uterine lining implantation 1. An ovum is released 22.8 Human embryos Development of embryo 3placenta umbilical cord 2 uterine lining 6 1 embryo amniotic fluid 4 5 amnion cervix7 vagina 8 22.8 Human embryos umbilical cord Carries CO2 & wastes towards the placenta umbilical artery embryo 22.8 Human embryos Carries O2 , food & antibodies to the foetus umbilical vein umbilical artery embryo 22.8 Human embryos CO2 & wastes diffuse from foetal blood into maternal blood O2 ,nutrients & antibodies diffuse from maternal blood into foetal blood maternal blood capillary of foetus 22.8 Human embryos Placenta Place for material For nutrition, exchange breathing and excretion of the between foetus foetus & mother 22.8 Human embryos Adaptations of placenta 1 Placenta possesses many finger-like projections called villi To increase the surface area for exchange of materials by diffusion 22.8 Human embryos 2 Thin membrane between maternal and foetal blood To decrease the distance for faster diffusion of materials across it 22.8 Human embryos 3 Maternal and foetal blood are separated To prevent the entry of germs from maternal blood to foetus blood 22.8 Human embryos 3 Maternal and foetal blood are separated To prevent the high pressure in maternal blood from damaging the delicate blood vessels of the foetus 22.8 Human embryos 3 Maternal and foetal blood are separated To prevent mixing of blood if the blood groups of mother and foetus are incompatible 22.8 Human embryos The foetus requires about 40 weeks (about 280 days) of development gestation period 22.9 The birth process The 22.9 The birth process 1 Uterus muscles contract rhythmically and powerfully 2 Cervix dilates 22.9 The birth process 3 Amnion breaks Amniotic fluid flows out through the vagina Lubricates the passage for foetus to come out 22.9 The birth process 4 Continuous contraction of uterus muscles Push the foetus out through the vagina 22.9 The birth process Once the baby has come out its umbilical cord is clamped & then cut The scar becomes the navel 22.9 The birth process After birth, placenta becomes detached from the wall of the uterus a few hours after the birth of baby & passes out through the vagina This is called afterbirth 22.10 Parental care 22.10 Parental care The parents not only provide the babies with food, clothes & shelter but also teach the young children how to look after themselves This increases the chance of survival of the young before they become mature 22.10 Parental care After birth, the baby has a natural instinct to suck It stimulates the breasts of the mother to release milk This process is called lactation 22.10 Parental care The advantages of breast-feeding 1 Human milk is uniquely suited for human babies Human milk is easy to digest & contains most of the essential nutrients It contains antibodies which help the baby to resist infection 22.10 Parental care The advantages of breast-feeding 2 Breast-fed babies are healthier Antibodies in human milk help to reduce the incidence of bacterial infections Breast-fed babies are less likely to have diarrhoea 22.10 Parental care The advantages of breast-feeding 3 Breast-feeding keeps women healthier Breast-feeding helps mothers recover from childbirth It is believed to reduce the risk of breast and ovarian cancers 22.11 Birth control 22.11 Birth control Human population is growing rapidly Run out of resources, pollution, overcrowding, …… Contraceptio n helps to reduce the growth of human population 22.11 Birth control Body temperature (℃) A B C Menstruation Why? A C Which period(s) is/are safe Day of the menstrual cycle for intercourse without fertilisation? 22.11 Birth control Body (℃) 1 temperature Ovulation Natural (rhythm) method A B C Menstruation NOT RELIABLE!!! A C It is because ovulation is most likely to Day of the menstrual cycle take place in period B 22.11 Birth control 2 Contraceptive pills Synthetic hormones prevent ovulation Many side effects water retention, high blood pressure, getting fatter, cardiovascular diseases, headaches 22.11 Birth control 3 Barrier method A device that prevents the sperms & egg from coming into contract with each other Female Male Diaphragm Condom Female condom 22.11 Birth control 3 Barrier method uterus Diaphragm (a dome-shaped rubber) fits over the entrance of the uterus 22.11 Birth control 4 Surgical method (or sterilisation) Male Female Vasectomy Tubal ligation Do not affect the formation of gametes and sex hormones 22.11 Birth control 4 Surgical method Sperm ducts are cut & tied The semen contains no sperm Vasectomy 22.11 Birth control 4 Surgical method Tubal ligation Sperm cannot reach the egg Tubal ligation 22.11 Birth control 5 Intrauterine devices (IUD) A small plastic or copper device is put into the uterus Prevent fertilised egg from implanting in the uterine wall 22.11 Birth control Summary 1 Natural (rhythm) method 2 Contraceptive pills 3 Barrier method 4 Surgical method 5 Intrauterine devices (IUD) Mind Map Reproduction two types asexual reproduction in bacteria binary fission sexual reproduction in flowering plants vegetative propagation examples of perennating organs 1. bulb 2. corm 3. rhizome 4. tuber Mind Map sexual reproduction in flowering plants in humans pollination sexual intercourse fusion of fusion of male gamete (inside pollen grain) male gamete (sperm) and and female gamete (ovum) female gamete (ovum) this process is called fertilisation fertilisation not occurs menstruation Mind Map fertilisation produces produces a fruit zygote prevention of this process in human birth control contains seeds implantation becomes contain embryo grows to new plants pregnant develops to baby needs parental care methods are called contraceptive methods