Exercise Questions
Question 1. Fill in the blanks:
(a) Production of new individuals from the vegetative part of parent is called_____________.
(b) A flower may have either male or female reproductive parts. Such a flower is called_____________.
(c) The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as _____________.
(d) The fusion of male and female gametes is termed as _____________.
(e) Seed dispersal takes place by means of _____________, _____________ and _____________.
Solution 1.
(a) Production of new individuals from the vegetative part of the parent is called vegetative propagation.
(b) A flower may have either male or female reproductive parts. Such a flower is called a unisexual flower.
(c) The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as Pollination.
(d) The fusion of male and female gametes is termed as fertilisation.
(e) Seed dispersal takes place by means of wind, water and animals.
Question 2. Describe the different methods of asexual reproduction. Give examples.
Solution 2. Following are the different methods of asexual reproduction:
Vegetative Propagation
In this method, new plants are produced from vegetative parts of the individual plants like roots, stems, leaves and buds.
Examples – Tuber of potato, the rhizome of ginger.
Budding
In this method of reproduction, the bud is a small bulb like projection which grows and gets detached from the parent cell and forms a new yeast cell. The new yeast cell grows, matures and produces more yeast cells.
Example – Yeast.
Fragmentation
In this mode of reproduction, the growth and multiplication are done by rapid break down of algae into two or more fragments. when water and nutrients are available each fragment of algae grows into new individuals.
Example – Algae
Spore Formation
Spores are the asexual reproductive part that is covered by a protective coat. This under favourable conditions germinates and develops into a new individual.
Examples – Fungi like Rhizopus, Mucor, etc.
Fission
In this method of reproduction, the unicellular organism splits to form new organisms. There are two types of fission which are
- Binary fission
- Multiple fission
Examples
Amoeba, paramecium, Leishmania etc. are examples of binary fission.
Plasmodium is an example of multiple fission.
Question 3. Explain what you understand by sexual reproduction.
Solution: In Sexual reproduction male and female gametes fuse to form a new individual. Stamens and pistils are male and female reproductive organs in plants which has the anthers and ovary respectively.
Question 4. State the main difference between asexual and sexual reproduction.
Solution 4.
| Asexual reproduction | Sexual reproduction |
| It involves only one parent. | It involves male and female parents. |
| Offsprings are identical to parents and to each other. | offsprings are not identical to the parents. |
| Male and female reproductive organs are not required. | Male and female reproductive organs are required. |
| Seeds are not needed. | Seed are needed. |
| Ex: Yeast, rose, jasmine | Ex: Insects, animals |
Question 5. Sketch the reproductive parts of a flower.
Solution 5.
Question 6. Explain the difference between self-pollination and cross-pollination.
Solution 6.
| Self-pollination | Cross-pollination |
| In self-pollination, pollen grains are transferred from the anther to the stigma of the same flower to other flower of same plant. | In cross-pollination transfer of pollen grains are done between flowers of other plants of same species. |
| Self-pollination occurs only in bi-sexual flowers like wheat, peas etc. | Cross pollination can occur in both unisexual and bisexual plants |
Question 7. How does the process of fertilisation take place in flowers?
Solution 7. After pollination, the male gametes of plants that is the pollen grains reach to the female gametes of plants which is the stigma and then to the ovary and after their fusion, they form a zygote. This process is called fertilization.
Question 8. Describe the various ways by which seeds are dispersed.
Solution 8. Following are the ways by which seeds can be dispersed:
- Some seeds that are lightweight or have hair-like structures can be dispersed by wind. For example drumsticks and maple.
- Some seeds that have the floating ability are dispersed by water. For example coconut.
- Some seeds that have hook-like structures are dispersed by animals by sticking to their body. For example urena
- Some seeds burst and seeds are scattered far from the parent plant. For example balsam.
Question 9. Match items in Column I with those in Column II: Column I Column II
| Column-I | Column-II |
| (a) Bud | (i) Maple |
| (b) Eyes | (ii) Spirogyra |
| (c) Fragmentation | (iii) Yeast |
| (d) Wings | (iv) Bread mould |
| (e) Spores | (v) Potato |
| (vi) Rose |
Solution 9.
| Column-I | Column-II |
| (a) Bud | (iii) Yeast |
| (b) Eyes | (v) Potato |
| (c) Fragmentation | (ii) Spirogyra |
| (d) Wings | (i) Maple |
| (e) Spores | (iv) Bread mould |
Question 10. Tick the correct answer:
(a) The reproductive part of a plant is the
(i) leaf (ii) stem (iii) root (iv) flower
(b) The process of fusion of the male and the female gametes is called
(i) fertilisation (ii) pollination (iii) reproduction (iv) seed formation
(c) Mature ovary forms the
(i) seed (ii) stamen (iii) pistil (iv) fruit
(d) A spore-producing organism is
(i) rose (ii) bread mould (iii) potato (iv) ginger
(e) Bryophyllum can reproduce by its
(i) stem (ii) leaves (iii) roots (iv) flower
Solution 10.
a) The reproductive part of a plant is the
Ans. (iv) flower
b) The process of fusion of the male and the female gametes is called
Ans. (i) fertilization
c) Mature ovary forms the
Ans. (iv) fruit
d) A spore-producing organism is
Ans. (ii) bread mould
e) Bryophyllum can reproduce by its
Ans. (ii) leaves