12. Reproduction in Plants Class 7 Science Solutions English Medium-NCERT Exercise

Exercise 

Q1. 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 _____________.

Answer:

(a) vegetative propagation.

(b) unisexual

(c) self pollination

(d) fertilisation

(e) air, water, insects  

Q2. Describe the different methods of asexual reproduction. Give examples.

Answer:

There are four different methods of asexual reproduction.

(i) Vegetative propagation: - In this the new plants are grown from vegetative parts of the plants like roots stems and leaves, since it is called Vegetative propagation. Ex: Potato, Sugarcane and rose.

(ii) Budding: - In yeast, there grow small bulb like projections called buds get detached from the parent cell and grow individuals. Ex: Yeast.

(iii) Fragmentation – Algae grow and multiply rapidly by fragmentation. An alga breaks up into two or more fragments. Ex; Algae.

(iv) Spore formation – Fungi reproduce by means of spores. A spore germinates and develops into a new individual. Ex; Fungi.

Q3. Explain what you understand by sexual reproduction.

Answer:

Such process of reproduction in which male and female gamates participate for reproduction is called sexual reproduction. New plants are obtained from seeds. Seeds grow in fruits by sexual reproduction. There are two kinds of flowers unisexual and bisexual which has 

Q4. State the main difference between asexual and sexual reproduction.

Answer:

Q5. Sketch the reproductive parts of a flower.

Q6. Explain the difference between self-pollination and cross-pollination.

Answer:

If the pollen lands on the stigma of the same flowers it is called self-pollination.

When the pollen of a lands on the stigma of another flower of the same plant, or that of the same kind, it is acalled pollination. 

Q7. How does the process of fertilisation take place in flowers?

Answer:

The cells which result after fusio of the gametes is called Zygote. The process of fusion of male and female gametes is called fertilisation which takes place in ovary the zygote take develops into an embryo later which develops into seeds.

Q8. Describe the various ways by which seeds are dispersed.

Answer:

(i) By the air and water.

(ii) Through insects and animal or attached to their bodies.

(iii) Bursting with sudden jerks.

Q9. Match items in Column I with those in 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

Answer:

10. Tick (9) 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 formatio

 (c) Mature ovary forms the (i) seed (ii) stamen (iii) pistil (iv) fruit

(d) A spore producing plant is

(i) rose (ii) bread mould (iii) potato (iv) ginger

(e) Bryophyllum can reproduce by its

(i) stem (ii) leaves (iii) roots (iv) flower

Answer:

(a) - (iv) flower

(b) - (i) fertilisation

(c) - (iv) fruit

(d) - (iii) bread mould

(e) - (ii) leaves