NOTES PREPARED BY
ASHAQ HUSSAIN BHAT
GL TEACHER SCHOOL EDUCATION
DEPARTMENT JAMMU AND KASHMIR
REPRODUCTION IN PLANTS
Points to Remember
Reproduction is production of new individuals from their parents
Flowers are reproductive part of a plant..
Roots, stems and leaves are vegetative parts of a plant.
Asexual and sexual reproduction are two types of reproduction found in plants.
Sugarcane, potatoes, roses etc. have no seeds. They reproduce asexually.
Reproduction through vegetative parts of plant is known as vegetative propagation.
Vegetative propagation needs less time to cultivate and produces exact copies of the parent plant.
Seeds are produced by sexual reproduction.
Unicellular yeast reproduces by budding. Cutting, fragmentation, spore formation are other asexual
reproductive methods.
Stamens and pistils are respectively male and female reproductive parts in a flower.
Flowers may be unisexual or bisexual.
The transfer of pollen grains from the anther to stigma of a pistil is called pollination.
Pollination is of two types-(i) self-pollination and (u) cross- pollination.
The process of fusion of male and female gametes to form a zygote is called fertilization.
Fruit is a ripened (mature) ovary.
Some fruits are fleshy and soft while others are hard.
Seeds are dispersed to different places by wind, water and animals.
SOME IMPORTANT DEFINITIONS
Reproduction. The production of new individuals from their parents.
Vegetative propagation. Reproduction in plants through vegetative parts such as stem, root, leaves and buds.
Unisexual flowers. The flowers which have either only the pistil or only the stamen are called unisexual flowers.
Bisexual flowers. The flowers which have both stamens and pistil are called bisexual flowers.
Pollination. The transfer of pollen grains from anther to the stigma of a pistil is called pollination.
Self-pollination. Landing of pollens on the stigma of pistil of the same flower is called self-pollination.
Cross-pollination. Landing of pollen grains from one flower on the stigma of another plant of the same kind is called cross-pollination.
Fertilization. The process of fusion of male and female gametes to form zygote is called fertilization.
Zygote. A cell formed by fusion of male and female gametes is called zygote (a fertilized egg).
Fruit. It is a ripened ovary in which developing embryo lies inside seeds.
Asexual Reproduction. Reproduction that does not involve the union of male and female gametes.
Sexual Reproduction. Reproduction that involves the union of male and female gametes.
Binary fission. Formation of two individuals from a single parent.
Embryo. The zygote develops into a structure called embryo.
Regeneration. The ability of living beings to repair their lost parts.
TEXT BOOK EXERCISES
1. Multiple choice questions - Tick mark (√) the correct choice.
1. The common method of reproduction in bacteria is:
(a) budding. b) Fragmentation
(c) binary fission. d) All the above
2. Budding is commonly seen in :
(a) Yeast b) grasses
(c) Amoeba d) Bryophyllum
3. Reproduction or propagation by stem is common in :
(a) Rose. c) Sweet potato
b) Potato d)Bryophyllum.
4. Unisexual flowers are found in :
(a) Mulberry b)Mustard
(c) Pean a d) Sunflower
5. A seed consists of:
(a) Embryo
(b) Seed coat and cotyledons
(c) Embryo and seed coat
(d) Seed coat and endosperm.
6. An embryo of a seed consists of:
a) Pleumule
b) Radicle, plumule and cotyledons
(c) Plumule and radicle
(d) Radicle and cotyledons.
Ans.
(1) (c) Binary fission
(2) (a) Yeast
(3) (b) Potato
(4) (a) Mulberry
(5) (c) Embryo and seed coat
(6) (b) Radicle, plumule and cotyledons.
2. Fill in the blanks :
(a) Budding is a kind of............. reproduction
(b) The amount of cytoplasm in the parent cell is............than the amount in the bud.
(c) Yeast cells reproduce by............
(d) Binary fission produces cells of.......... Size
(e) Budding produces cells of ............ size.
f)Fungi, ferns and mosses reproduce by............
(g) Male sex cells in plants are called................
(h) The two kinds of pollination are .......and........
Ans. (a) asexual
(b) more in
(c) budding
(d) equal
(e) unequal
(f) spore formation
(g) pollen grains
(h) self, cross.
3.State whether the statement given below are true or false
(a) Asexual reproduction is more common than the sexual reproduction.
(b) Producing life is called respiration.
(c) Bacteria and yeast reproduce by asexual reproduction.
(d) Reproduction by spores is a method of asexual reproduction
(e) A potato tuber is really an underground stem.
(f)A whole new plant can grow from the eye of a tuber.
(g)Cutting and grafting are natural means of reproduction.
(h) Most organisms have the capacity of regeneration in some or the other ways.
(i) Stamens make eggs cells.
(j) A fertilized egg becomes a seed.
(k) Flowers which possess stamens and pistils are called unisexual.
(l) Insect pollinated flowers are brightly coloured.
Ans.
(a) False
(b) False
(c) True
(d) True
(e) True
(f) True
(g) False
(h) False
(i) False
(j) True
(k) False
(l) True
4. Differentiate between the following:
(i) Asexual reproduction and sexual reproduction.
(ii) Binary fission and budding.
(iii) Self-pollination and cross-pollination.
(iv) Insect pollinated flowers and wind pollinated flowers.
(v) Zygote and embryo.
Ans. (i) Differences between asexual and sexual
Asexual Reproduction
(1) The process involves only one cell or one parent.
(2) The whole body of the parents may act as reproductive unit or it can be single cell or a bud
(3) Only mitotic division takes place.
(3) Meiosis and fertilization
(4) No formation of sex organ.
Sexual Reproduction
(1) This process involves two cells or gametes belonging to either the same or different parents.
(2) The reproductive unit is called gamete which is unicellular and haploid.
(4) Formation of sex organs is essential.
(ii) Differences between binary fission and budding
Binary fission
(1) An organisms divides into two
(2) It produces cells of the same size.
(3) Examples are amoeba, bacteria etc.
Budding
(1) A single bud grows into a single new individual.
(2)It produces cells of unequal size.
(3) Examples are hydra, yeast etc
(iii) Differences between self-pollination and cross- pollination
Self-pollination
(1) It occurs within a flower plants or the same species.
Cross-pollination
(1) It occurs between two flowers borne on different plants or the same species.
(2) Agents such as insects, water and wind are required for ensuring pollination.
(iv) Differences between insect pollinated flowers Wind pollinated flowers
Insect pollinated flowers
(1) These flowers brightly coloured.
(2) These flowers may not produce so many pollen grains
(3) These flowers secrete a nectar or honey
Wind pollinated flowers
(1) These flowers are not brightly coloured.
(2) These flowers produce many pollen grains.
(3) These flowers do not have have nectar or honey
(v) Differences between zygote and embryo
Zygote
(1) It is a structure formed by the union of male and female gametes.
(2) It is a single celled structure.
Embryo
(1) Zygote during development grows into an embryo.
(2) It is a multicellular structure
5. Find the odd one out, giving reasons:
(i) Gamete, budding, fragmentation, regeneration
(ii) Cutting, grafting, layering, binary fission.
(iii) Ovary, stigma, style, pollen grain.
Ans. (i) Gamete. Because all others terms are methods of asexual reproduction.
(ii) Binary fission. Others terms are the artificial methods of vegetative propagation.
(iii) Pollen grains. All other terms are parts of a carpel of a flower (Female sex organ).
6. Name the following:
(i) Part of the flower where ovule is found.
(ii) Three agents of pollination.
(iii) The place where fertilization occurs in the flowering
Ans. (i) Carpel.
(ii) Animals, wind, water.
(iii) Ovary of the carpel.
7. Mention the functions of the following
(i) Flower (iii) Ovary
(ii) Anther (iv) Stigma
(v) Seed dispersal
Ans. (i) Functions of flower. Flower helps in the sexual reproduction. It produces seeds and fruits. It is the sexual of the plant. It produces the male gametes.
(ii) Functions of anther. Anther is the swollen structures of the stamen It produces the male gametes.
(iii) Functions of ovary. Ovary is the basal part of a pistil. It contains ovules which have female gametes.
(iv) Functions of stigma. Stigma is the upper knob-like part of the pistil. It receives the pollen grains from the anthers.
(v) Functions of seed dispersal. Seed dispersal is necessary for the germination of seeds. A seed must fall on a suitable place for its germination.
8. Answer the following questions
Q1. Why is reproductions necessary for living organisms?
Ans. Reproduction means creating new life, producing young ones of their own kind. If they would not reproduce, there would be no organism left. The species would thus perish. So, reproduction is necessary for the perpetuation of species.
Q2. How much of the parents nuclear material does each daughter cell gets during reproduction by binary fission?
Ans. During reproduction by binary fission each daughter cell gets half of parents nuclear material.
3. What kind of reproduction is binary fission?
Ans. Binary fission is an asexual kind of reproduction.
Q4. How many parents take part in binary fission
Ans. Only one parent takes part in binary fission.
Q5. Describe the various methods of asexual reproduction.
Ans. Methods of asexual reproduction.
(i) Binary fission
(iii) Fragmentation
(v) Regeneration
(ii) Budding
(iv) Spore formation
(vi) Vegetative propagation
(i) Binary fission. It is a common method of reproduction divides into two equal parts. Nucleus also divides in two in unicellular organisms like bacteria etc. The parent cell parts. One daughter nucleus goes into one of the two parts then grows into full size and behaves as daughter cell. Each independent individual.
Fig. Binary fission in bacteria
(ii) Budding. It is a common method of reproduction in Sponges, yeast and Hydra. In this process, the new individual develops from a small outgrowth called bud on the surface of parent. The bud detaches from the parent body and grows to full size and becomes a new individual.
 |
| budding in yeast |
(iii) Fragmentation. It occurs in filaments of algae like spirogyra. Each filament breaks up into two or more fragments which grow in to the new individual
(iv) Spore formation. An individual produces spores which during favourable conditions give rise to new individuals eg. Mucor. (a fungus).
 |
| spore formation in mucor (a fungus) |
(v) Regeneration. It is a form of fission in which a parent individual divides into a number of parts, each of which regenerates the missing structures to form a whole organism. It occurs in flatworms, ribbon worms, annelids, grasses etc.
(v) Vegetative propagation. A part of plant body like stem, root or leaf other than reproductive organ gives rise to new individual plant e.g. Rose stem cutting gives to new rose plant. No seeds are produced in this method.
Q. 6. Describe the various methods of vegetative propagation.
Ans. Vegetative Propagation. In this method any vegetative part (stem, root, leaf or branches) other than sexual part of plant takes part and gives rise to new plants. It is of the following types.
(a) By Root. The roots of dahlia, sweet potato, asparagus etc. are swollen due to storage of food material. When these roots are buried in the soil, they grow into new plants.
 |
| Roots in dahlia |
(b) By Stem. In some plants like potato, sugarcane and ginger etc. the asexual reproduction takes place by stem. e.g. Potato is an underground stem (tuber). Each tuber is swollen due to food storage and has a number of buds called eyes. Each eye germinates and give rises to a new plant.
Fig. A sprouted potato tuber showing the development of many plants
(c) By Leaves. Some plants like Bryophyllum and Begonia reproduce by leaves. Bryophyllum plants have buds margins of their leaves. Plantlets develop On being detached, the plantlets develop into independent plants
 |
| Bryophylum leaf |
Q. 7. Mention two characteristic features of wind pollinated flowers.
Ans. (i) The flower of maize plant have pollen grains which are very small in size and dry. Such pollen grains can be easily blown away by wind.
(i) The wind blown pollen grains are caught easily by the stigmas which hang out.
Q. 8. Mention two features of insect pollinated flowers
Ans. Features of insect pollinated flowers
(i) The flowers have nectar or honey at their bases.
(ii) The flowers are large, showy and coloured e.g. sunflower, china-rose and salvia.
Fig. Pollination by Insects
Q. 9. Describe the various steps leading to the formation of seeds in plants.
Ans. The transference of pollen grains from anther to stigma is called pollination. The stamens in flower have anthers which produce pollen grains. Gynaecium or pistil bears
 |
| Gynoecium at the time of fertilization |
Q. 10. Describe the various ways by which seeds are dispersed.
Ans. Seed are dispersed by following ways:
(i) By water
(ii) By wind
(iii) By animals
(iv) By bursting (Explosion).
(i) By water. Some seeds develop floating ability in form of spongy or fibrous outer coat e.g. coconut.
(ii) By wind. Some seeds have wings or hairy outgrowth
with which they get dispersed by wind e.g. maple, oak and sunflower etc.
(iii) By animals. Seeds with spines or hooks get attached to animals and get dispersed e.g. xanthium.
(iv) By bursting. (Explosion). In this process, the ripened fruit bursts open to spread seeds e.g. castor, balsam.
Q. 9. Spell the missing word:
Fill in the missing letters to spell the terms that fit the definition.
(1)......t........g........a (a) top part of pistil
ii.........g....... (b) Female gamete
iii.........m.....r.....o (c) Baby plant
iv........u........d.....n.... (d) Method of asexual reproduction
Ans. (i) Stigma. ii Egg
(iii) Embryo iv .Budding
Q. 10. Spot the odd term.
In each of the following set one terms does not belong to the set. Circle that term.
(i) Sexual reproduction, asexual reproduction ,one parent
(ii) Sexual reproduction, asexual reproduction, two parents
(ii) Binary fission, bacteria:, yeast
(iv) Binary fission ,budding , yeast
(v) Stamen, anther, style
Ans.
(i) Sexual reproduction (ii) Asexual reproduction
(iii). yeast (iv).style
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