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REPRODUCTION
IN PLANTS
12
TEXTBOOK QUESTIONS AND THEIR ANSWERS
Q.1. Paheli has never seen the seeds of sugarcane, potato and
rose. She wants to know how these plants reproduce.
Ans. The above plants reproduce by means of asexual reproduction.
1. In asexual reproduction, plants can give rise to new plants
without seeds.
2. So, new plants are produced from roots, stem, leaves and
buds.
3. In sugarcane and rose, new plants develop from stems
while in potato, new plants develop from eyes or buds.
Q.2. Bhoojho wants to know if there is any advantage of
vegetative propagation.
Ans. Plants produced by vegetative propagation. It takes less time to
grow and bear flowers and fruits earlier than those produced
from seeds.
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Q.3. Boojho wants to know how the male gamete in the pollen
grain reaches the female gamete present in the ovule.
Ans. By the process of pollination.
Q.4. Boojho wants to know why flowers are generally so
colourful and fragrant. Is it to attract insects ?
Ans. Most of the flowers are highly coloured and strong smelling to
attract insects, which help in the process of pollination.
Q.5. 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
___ .
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(e) Seed dispersal takes place by means of ___________
and _____.
Ans. (i)
Vegetative
propagation,
(ii)
Unisexual
flower,
(iii) Cross-pollination, (iv) Fertilization, (v) Wind, water,
animals.
Q.6. Describe the different methods of asexual reproduction.
Give examples.
Ans. There are several methods of asexual reproduction such as
vegetative propagation, budding, fragmentation and spore
formation.
(a) Vegetative propagation : In this type of asexual
reproduction new plants are produced from the roots,
stem, leaves and buds. For examples, rose, sugar cane,
money plant etc.
(b) Budding : In the yeast plant, small bulb like projections
come out from the yeast cell which are called bud. The
bud gradually grows and gets detached from the parent
cell and forms a new yeast cells. The new yeast cell
grows, mature and produces more yeast cells. This process
is called budding.
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(c) Fragmentation : In this type of asexual reproduction,
algae grow and multiply rapidly by fragmentation with the
availability of water and nutrients. An alga breaks up into
two or more fragments. These fragments or pieces grow
into new individuals.
(d) Spore formation : In this type of asexual reproduction
fungi grow from spores. The spores are asexual
reproductive bodies. Each spore is covered by a hard
protective coat to withstand unfavourable conditions such
as high temperature and low humidity. Under favourable
conditions, a spore germinates and develops into a new
individual. Plant such as moss and fern also reproduce by
means of spores.
Q.7. Explain what do you understand by sexual reproduction.
Ans. In sexual reproduction, both male and female parts take part in
the reproduction. In this process, a male and a female gamete
fuse to form a zygote. Thus, for sexual reproduction two
parents are required to produce one new individual.
Q.8. State the main difference between sexual and asexual
reproduction.
Ans.
Sexual reproduction
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Asexual reproduction
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1. New plants are
obtained from seeds.
2. Two parents are
required to produce an
individual.
3. Takes place with the
help of specialized
cells.
4. New individual has
characters of both the
parents.
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1. Plants can give rise
to
new
plants
without seeds.
2. The new individual
comes from a single
parent.
3. No cells are
required.
4. Characters of the
new individual are
same as that of the
only parent.
Q.9. Sketch the reproductive parts of a flower.
Ans.
Q.10. Explain the difference between self-pollination and crosspollination.
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Ans.
Self pollination
Cross pollination
1. In self-pollination,
pollen grains are
transferred from the
anther to the stigma
of the same flower.
2. In self-pollination,
no agency is
required.
3. Occurs only in
bisexual flowers.
1. In cross-pollination,
pollen grains are
transferred from the
anther of one flower
to the stigma of
another flower of the
same kind.
2. Agencies like wind,
air or insects are
required.
3. Occurs in both
unisexual and
bisexual flowers.
Q.11. How does the process of fertilization take place in flowers ?
Ans. Pollen grain reaches on the stigma of pistil by pollination. On
the stigma, the pollen grain germinates and a pollen tube
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comes out. This pollen tube grows and approaches through the
style to ovary carrying male gametes with it, where it enters
the ovule. Inside the ovule, there is female gamete or egg. The
male, gamete fuses with the female gamete. This process is
called fertilization.
Q.12. Describe the various ways by which seeds are dispersed.
Ans. Seeds and fruits of plants are carried away by wind, water and
animals. Winged seeds such as those of drumstick and maple,
light seeds of grasses or hairy seeds of aak (Madar) get blown
off with the wind to far away places. Some seeds are dispersed
by water. These seeds usually develop floating ability in the
form of spongy fibrous outer coat as in coconut. Some seeds
are dispersed by animals, especially spiny seeds with hooks
which get attached to the bodies of animals and are carried to
distant places. Some examples are Xanthium and Urena.
Some seeds are dispersed when the fruit burst with sudden
jerks. The seeds are scattered far from the parent plant.
Examples, caster and balsam.
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Q.13. 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
Ans. 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
Q.14. Tick (9) the correct answer :
(a) The reproductive part of the plant is the
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(i) leaf
(ii) stem
(iii) root
(iv) flower
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Ans. (iv) Flower.
(b) The process of fusion of the male and the female
gametes is called
(i) fertilization
(iii) reproduction
(ii) pollination
(iv) seed formation
Ans. (i) Fertilization.
(c) Mature ovary forms the
(i) seed
(iii) pistil
(ii) stamen
(iv) fruit
Ans. (iv) Fruit.
(d) A spore producing plant is
(i) rose
(iii) potato
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(ii) bread mould
(iv) ginger
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Ans. (ii) Bread mould.
(e) Bryophyllum can reproduce by its
(i) stem
(ii) leaves
(iii) roots
(iv) flower
Ans. (ii) Leaves.
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