Samacheer Kalvi 7th Science Term 1 Solutions Chapter 5 Pdf
Tamilnadu Board Samacheer Kalvi 7th Science Term 1 Solutions Chapter 5: Tamilnadu State Board Solution Class 7 Science Term 1 Chapter 5 – Reproduction and Modification in Plants.
Samacheer Kalvi 7th Science Term 1 Solutions Chapter 5: Overview
|
Board |
Samacheer Kalvi |
| Class |
7 |
|
Subject |
Science |
| Chapter |
5 |
|
Chapter Name |
Reproduction and Modification in Plants |
Samacheer Kalvi 7th Science Term 1 Solutions Chapter 5 Pdf
Reproduction and Modification in Plants
Chapter 5
I.) Choose the appropriate answer.
1.) Vegetative propagation by leaves takes place in
a.) bryophyllum
b.) fungi
c.) virus
d.) bacteria
Answer : a.) bryophyllum
Solution : In bryophyllum vegetative propagation take place through leaf. Leaf notches of bryophyllum contains buds that germinate to new plants when they come in contact with soil.
2.) Asexual reproduction in yeast is
a.) spore formation
b.) fragmentation
c.) pollination
d.) budding
Answer : d. budding
Solution : In budding a small protuberance which gradually grow and detach from the parent cell. Budding is seen in yeast.
3.) Reproductive part of a plant is
a.) root
b.) stem
c.) leaf
d.) flower
Answer : d.) flower
Solution : Flower is the reproductive part of plant.
4.) Pollinators are
a.) wind
b.) water
c.) insect
d.) All the above
Answer : d. All the above
Solution : Pollinators are the agents that helps in pollination . eg wind , water, insect ,birds and animals.
5.) Climbing roots are seen in
a.) betel
b.) black pepper
c.) Both of them
d.) None of them
Answer : c.) Both of them
Solution : In betel and black pepper, nodes or internodes bear roots which help in climbing.
II.) Fill in the blanks.
1.) The male reproductive part of a flower is stamen.
2.) ovary is the basal swollen part of the gynoecium.
3.) After fertilization the ovule becomes seed.
4.) Breathing roots are seen in mangrove plants.
5.) Onion and garlic are example for bulb
III.) State true or false. If false, correct the statement.
1.) A complete flower has four whorls.
Answer : True
2.) The transfer of pollen to the stigma is known as pollination.
Answer : True
3.) Conical shaped root is carrot.
Answer : True
4.) Ginger is an underground root.
Answer : False
Correct statement : Ginger is an underground Stem.
5.) Leaves of aloe vera are fleshy and store water.
Answer : True
IV.) Match the following
| Petal | Attracts insect |
| Fern | Spore |
| Phylloclade | Opuntia |
| Hooks | Bignonia |
| Sucker | Chrysanthemum |
V.) Answer very briefly.
1.) Write two types of reproduction in plants.
Answer : The two types of reproduction in plants :
i) sexual reproduction
ii) asexual reproduction
2.) What are the two important parts of a flower?
Answer : The two important parts of a flower are Androecium and Gynoecium.
3.) Define – Pollination.
Answer : The process by which pollen grains reach stigma is called as pollination.
4.) What are the agents of pollination?
Answer : Agents of pollination are wind, water, insects ,birds and animals
5.) Give example for Corm and Tuber
Answer : Example of Corm is Colocasia.
Example of tuber is Potato.
6.) What is tendril?
Answer : In climbers, the leaf of plant are modified into elongated structure to help the plants climb efficiently. These modification is known as tendril.
7.) What are thorns?
Answer : Thorns are pointed, rigid modification of leaves or other part of plant Which helps in excess loss of water and protect from enemies.
VI.) Answer briefly.
1.) Differentiate bisexual flower from unisexual flower?
Answer :
| Bisexual flower |
Unisexual flower |
| Flowers having both androecium and gynoecium are called bisexual flowers. For example – lily,rose,hibiscus. | Flowers having either androecium or gynocium are called unisexual flowers. For example – papaya,watermelon. |
2.) What is cross pollination?
Answer : The process of transfer of pollen grains from the anther of one flower to the stigma of another flower of the same kind or different plant is known as cross pollination.
3.) Write notes on phyllode.
Answer : Phyllode is the modified leaf like structure formed from petioles. For example in Acacia auriculiformis. Phyllode perform the function of leaves i.e photosynthesis.
VII.) Answer in detail.
1.) Write a brief account on pollination.
Answer : The process by which pollen grains transfer to stigma is called as pollination. The flower that receives pollen grains is called pollinated flower.
Pollination is of two types : i) self pollination ii) cross pollination
In self pollination pollen grains are transferred from the anther to the stigma of the same flower or to another flower of the same plant whereas in cross pollination pollen grains are transferred from the anther of one flower to the stigma of another flower of the same kind or different plant. Many pollinators helps in pollination like bees, insects, birds, wind, water and animals.
2.) Explain the underground stems.
Answer : Usually stem grows above the ground, but there are some stems that
Modified and grow under the ground to store food. These underground stems swell and become thick. There are four types of underground stems. They are: 1.) Rhizome 2.) Corm 3.) Tuber 4.) Bulb
1.) Rhizome : It is an underground thick stem with nodes and internodes . It grows horizontally and has an irregular shape.
E.g. Ginger and Turmeric
2.) Corm : It is an underground stem that is round in shape and flat at the top and bottom. E.g. Colocasia
3.) Tuber : It is an enlarged, spherical underground stem that stores food. It has many dormant buds on its surface known as ‘eyes’. If we plant a part of tuber with the bud, it grows into a new plant. E.g. Potato
4.) Bulb : It is a condensed stem which is disc like and stores food in the fleshy leaves. The bulb has two types of leaves i. e Fleshy Leaves and Scaly Leaves. E.g. onion and garlic.
VIII.) Higher Order Questions.
1.) Ginger is considered to be a stem, not a root. Why?
Answer : Ginger is rhizome type of underground stem .It has nodes and internodes with scale leaves at the node. It grows horizontally and has an irregular shape. Therefore, ginger is considered to be a stem, not a root.
2.)What will happen if pollen grain of rose gets deposited on stigma of lily flower? Will pollen germination takes place? Why?
Answer : No, pollen germination will not take place because pollen of same species get fused with ovule. Pollen of rose plant will germinate on stigma of rose plant.
IX.) Consider the following statements and choose the correct one.
1.) Assertion: Pollination and fertilization in flowers produce fruits and seeds.
Reason: After fertilization the ovary becomes fruit and ovule becomes seed.
Answer : c. Assertion is correct, Reasoning is correct.
2.) Assertion: An example for conical root is carrot.
Reason: It is an adventitious root modification.
Answer : d. Assertion is correct, Reasoning is incorrect.
X.) Picture based question.
i.) Label the picture given below.
Answer :
ii.) Identify the four plants shown in the following table. Name the different modifications in each of them.
| Name |
Modification |
| Garlic | Underground stem [bulb] |
| Turnip | Tap root [storage of food] |
| Rose plant | Stem [cutting] |
| Maize | Stilt root |
