Reproduction in Plants Class 7 Extra Questions and Answers

These AP 7th Class Science Important Questions and 8th Lesson Reproduction in Plants Class 7 Extra Questions will help students prepare well for the exams.

Class 7 Science Reproduction in Plants Extra Questions

Reproduction in Plants Class 7 Important Questions

Question 1.
What is meant by reproduction?
Answer:
The process of producing a new organism from the existing organism (or the parent) of the same species is called reproduction.

Question 2.
What is pollination?
Answer:
Pollination is a process in which pollen grains get transferred from anther to the stigma of the flower.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 3.
Which type of pollination does the given figure indicate ?
Answer:
The type of pollination is self-pollination. If the ‘pollen’ is transported from the ‘anther’ of any flower to the ‘stigma’ of same flower, it is termed as ‘Self-Pollination’.
Reproduction in Plants Class 7 Extra Questions and Answers 1

Question 4.
Pick the odd one out from the following on the basis of mode of reproduction and give reason for it. Sugarcane, Potato, Rice, Rose.
Answer:
The odd one out is rice. Sugarcane, potato and rose reproduce through vegetative propagation. Whereas rice reproduces by sexual reproduction.

Question 5.
What do you mean by vegetative propagation?
Answer:
Vegetative propagation is the ability of plants to reproduce by using vegetative parts like root, stem and leaves.

Question 6.
Why reproduction is essential for life process?
Answer:
Reproduction is essential for continuation of the species from generation to generation.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 7.
What is Zygote?
Answer:
Zygote is a diploid cell formed from the fusion of male and female gametes.

Question 8.
Define pollination.
Answer:
The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination.

Question 9.
Name the various methods of asexual reproduction.
Answer:
Various methods of asexual reproduction are vegetative propagation, budding, fragmentation, spore formation.

Question 10.
What are pollen grains?
Answer:
Pollen grains are tiny spherical partules that contain the male gamete of a plant.

Question 11.
What is seed dispersal?
Answer:
The distribution or transfer of seeds from the place of their origin to a faraway place is known as seed dispersal.

Question 12.
What do you mean by fertilisation?
Answer:
The process in which the male gamete fuses with the female gamete to form a new cell (called zygote) is called fertilisation.

Question 13.
What is stamen?
Answer:
Stamen is a male reproductive organ of a plant. These are the little stalks with swollen top and lies inside the ring of petals. The stamen is made up of two parts, i.e., filament and another. The stalk of stamen is called filament and the swollen top of stamen is called anther.

Question 14.
Name any two hard fruits and any two fruits which are fleshy and juicy.
Answer:
Some fruits are hard like almonds and walnuts. Some fruits are fleshy and juicy such as mango and orange.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 15.
Define fragmentation.
Answer:
The process of asexual reproduction in which an organism breaks up into two or more fragments is called fragmentation. These fragments grow into new individuals.

Reproduction in Plants Extra Questions

Question 1.
In the figure given below, label the parts marked (a), (b) and (c)
Answer:
Reproduction in Plants Class 7 Extra Questions and Answers 2
The parts in the given figure can be labelled as follows: When a pollen grain falls on the stigma of a flower it grows into a pollen tube downwards through the style towards the egg in ovary. A male gamete moves down the pollen tube and fuses with female gamete in ovary to form a zygote.

Question 2.
Coconut is a large and heavy fruit. How is it adapted for dispersal by water?
Answer:
Coconut contains an outer fibrous layer which enables them to float in water.This means it can drift in water bodies to dissimilar locations for a long time period. This way coconut is adapted for dispersal by water.

Question 3.
What are bisexual and unisexual flowers?
Answer:

  • Unisexual flower: The flower which contains only one reproductive organ (i.e., either male or female) are called unisexual flowers. These are also called as an incomplete flower, E.g: papaya, watermelon, corn, cucumber, etc.
  • Bisexual flower: The flower that contains both reproductive parts (i.e., male and female) in a single flower are called a bisexual flower. These are also termed as hermaphrodites or complete flower, E.g: rose, mustard, hibiscus, etc.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 4.
How does seed dispersal benefit to plants?
Answer:

  • Seed dispersal avoids overcrowding of young plants around their parent plants.
  • It helps in preventing competition between the plants and its own seedlings for sunlight, water and minerals.
  • One of the benefits of seed dispersal is that it enables the plant to grow into new habitats for wider distribution and provides them with a better chance of survival.

Question 5.
Explain the types of reproduction in plants.
Answer:
There are two types of reproduction in plants. They are:

  • Asexual reproduction : In this mode of reproduction, new plants are produced without seeds by involvement of single parent. New plants grow by means of vegetative propagation, budding, fragmentation, or spore formation.
  • Sexual reproduction : In this mode of reproduction, new plants are produced through the formation of seeds. Male and female gametes fuse to form a zygote which later on develops into a seed. For example: Mango.

Question 6.
Write any three advantages of the vegetative propagation method.
Answer:
Following are the advantages of vegetative propagation:

  • It is a fast method of reproduction.
  • Plants produced by vegetative propagation have same features as that of parent plant.
  • Seedless plants can be easily propagated.

Question 7.
How do fungi, spirogyra, and yeast reproduce?
Answer:

  • Yeast reproduce by budding.
  • Spirogyra that are present in waterbodies reproduce by fragmentation.
  • Fungi reproduces asexually by spore formation.

Question 8.
How does an alga reproduce?
Answer:
Algae reproduce by a method known as fragmentation. The breaking down of filaments into fragments that grow into young ones is called fragmentation.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 9.
What are fruits? What are fleshy and dry fruits?
Answer:
Fruits are the ripened ovary of a flower. There are two types of fruits:

  • Fleshy fruits : The fruits are fleshy and juicy like oranges, mango, apple etc.,are called fleshy fruits.
  • Dry fruits: The fruits which are dry and hard like almonds and walnuts are called dry fruits.

Question 10.
How do plants such as mosses and ferns reproduce?
Answer:
Plants such as mosses and ferms are reproduced by means of spores. 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. Hence, spores can survive for a long time. Under favourable conditions a spore germinates and develops into a new individual.

Question 11.
What are the differences between fertilisation and pollination ?
Answer:

S.No. Pollination Fertilisation
1) The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination. Fertilisation is the fusion of male and female gametes of plants after a process of successful pollination.
2) It occurs only in flowering plants. It occurs in almost every plant in living organisms.
3) It takes place on the outer part of the flower i.e., external mechanism. It takes place inside the flower i.e., internal mechanism.
4) There is no formation of pollen tubes in the process of pollination. The pollen received from male anther and there is a transfer to the ovary by the pollen tube.
5) It takes place before the process of fertilisation. It takes place after the process of pollination.

Question 12.
Which part of a plant develops into the seed?
Answer:
The ovules within the ovary develop into the seeds of the plant. Each ovule that has transformed into a seed contains an embryo within it, which is protected by the walls of the ovule which develops into a hard shell.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 13.
How does fertilization occur in flower ? Where and how are seeds formed in plants?
Answer:
In asexual reproduction plants can give rise to new plants without seeds, whereas in sexual reproduction, new plants are obtained from seeds.

Extra Questions of Reproduction in Plants Class 7

Question 1.
Group the seeds given in figure (i) to (iii) according to their means of dispersion,
a) Seed dispersed by wind
b) Seed dispersed by water
c) Seed dispersed by animal
Reproduction in Plants Class 7 Extra Questions and Answers 3
Answer:
The seeds and their means of dispersal are :
a) Seed dispersed by wind: Seeds of maple

  • (winged seed which are light in weight) and seed of aak or madar
  • (hairy outgrowth, which makes it lighter) can be dispersed by wind.

b) Seed dispersed by water : Seeds having spongy form and floating ability which are dispersed by water to different places.

c) Seed dispersed by animals : Seed of Xanthium (iii) are spiny with on them which gets attached to the bodies of animals and are carried to distant places. None of the seed given in the figure is dispersed by water.

Question 2.
Explain the structure of a flower.
Answer:
Flowers are the reproductive parts of the plants. A typical flower consists of the following parts.
a) Sepals : These are the green leaf-like outermost circle of the flower. They help in the preparation of the food.

b) Petals : Petals are the colourful and most attractive part of the flower. These lie inside the sepals.These are scented and attract insects for pollination.

Reproduction in Plants Class 7 Extra Questions and Answers 4

c) Stamen : It is a male reproductive organ of a flower. There are two parts of stamen

  • anther and
  • filament. Anther contains pollen grains which have male gametes.

d) Pistil: It is the female reproductive part of the flowers. There are three main parts of the pistil. They are stigma, style and ovary. The ovary contains one or more ovules.The female gametes or the eggs are formed in an ovule.

Reproduction in Plants Class 7 Extra Questions and Answers

Question 3.
Explain different types of pollination found in flowering plants.
Answer:
Pollination : The transfer of pollen grains from the anther of a stamen to the stigma of a pistil is called pollination.
Pollination takes place in two different ways :

Reproduction in Plants Class 7 Extra Questions and Answers 1

  • Self-pollination : The transfer of pollen grains from the anther of a flower to the stigma of the same flower or another flower of the same plant is known as self-pollination or autogamy.
  • Cross pollination: The. transfer of pollen grains of a flower to the stigma of another flower of a different plant of the same species is called cross pollination or allogamy.

Question 4.
What is vegetative propagation? Describe vegetative propagation through different parts of the plant.
Answer:
Vegetative propagation is the ability of plants to reproduce by using vegetative parts like root, stem and leaves.
a) Vegetative propagation by roots : In some plants like sweet potato, dahlia, etc., a new plant develops through their roots and bulbs.

b) Vegetative propagation by leaves: In some plants leaves are hurried into the moist soil, the cut edges or margins of leaves develop a new plants that resemble to the parent, e.g. Bryopbyllum or sprout leaf plant.

c) Vegetative propagation by stems : In certain plants like potato, ginger, sugarcane etc, new plants grow from the stems of these plants. In potatoes these are small ‘eyes’ on the swollen stem. These eyes germinate to give rise to new plants. Ginger and turmeric also give rise to new plants from the small buds growing on their swollen stems.

Question 5.
Explain sexual reproduction in plants.
Answer:
Sexual reproduction occurs in plants having well developed reproductive parts in them. Flowers are the reproductive parts of the plant. Flowers can be unisexual i.e. having only male or female reproductive parts, and bisexual i.e., having both male and female reproductive parts.

Reproduction in Plants Class 7 Extra Questions and Answers

Female reproductive part of the flower i.e. the pistil form female ovules and male reproductive parts i.e., Androecium give rise to male gametes. When male and female gametes fuse in the ovary of the flower the process of fertilisation takes place. Male gametes are carried to the female flowers far away by agents like wind, water, insects and animals. This is called pollination. After fertilisation, the ovary of the flower becomes pulpy and juicy to form fruits. The ovules become the seeds.

Question 6.
In the figure of a flower given under, label the parts whose below and give their names.
Reproduction in Plants Class 7 Extra Questions and Answers 6
a) The part which contains pollen grains.
b) The part where the female gamete is formed.
c) The female reproductive part, where pollen grains germinate.
d) The colourful part of flower which attracts insects.
Answer:
The various parts of a flower whose functions are mentioned above are labelled as follows:
Reproduction in Plants Class 7 Extra Questions and Answers 5
a) The part which contains pollen grains Anther.
b) The part where the female gamete formed is Ovary.
c) The female reproductive part where pollen grains germinate is Stigma.
d) The colourful part of flower which attracts insects is Petals.

Case Based / Data – Based Questions

Stamens are the male reproductive part and pistil is the female reproductive part. Flowers which contain either only pistil or only stamens are called unisexual flowers. Flowers which contain both stamens and pistil are called bisexual flowers. Corn, papaya and cucumber produce unisexual flowers, whereas mustard, rose and petunia have bisexual flowers.

Both male and female unisexual flowers may be present in the same plant or in different plants. Anther contains pollen grains which produce male gametes. A pistil consists of stigma, style and ovary. Ovary contains one or more ovules. The female gamete or the egg is formed in an ovule. In sexual reproduction a male and a female gamete fuse to form a zygote.

a) What are the male and female reproductive part of a flowers?
Answer: Stamen and pistil are the male and female reproductive part of a flower.

Reproduction in Plants Class 7 Extra Questions and Answers

b) What are bisexual flowers?
Answer: Flowers which contain both stamens and pistil are çalled bisexual flowers.

c) Give any two examples of unisexual flowers?
Answer: Papaya, watermelon, corn, cucumber, etc., are examples of unisexual flowers.

d) How many ovules does an ovary contains?
Answer: Ovary contains one or more ovules.

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