Q1.  Give one word for each of the following questions :

1.  The insect that is used to obtain silk.
Ans:  Silkworm .

2.  The country that leads in silk production .
Ans:  China .

3.  Wool that is common in Tibet and Ladakh .
Ans:  Yak .

4.  The bacterium that causes sorter’s disease.
Ans:  Anthrax.

5.  Small fluffy  fibres that sometimes appear on our sweater.
Ans:  Burrs.

Q2.  State whether the following statements are true or false. Correct the statement if it is false.

1.  Wool is a poor conductor of heat.
2.  Pashmina shawls are obtained from Angora goats.
3.  Shearing of sheep is done during winters.
4.  In the processing of wool sorting is followed by scouring.
5.  Silk fibres are made of protein.
1.  True
2.  False. Pashmina shawls are obtained from Kashmiri goats.
3.  False. Shearing of sheep is done during hot weather.
4.  False. Scouring is followed by sorting.
5.  True.

Q3.  Answer the following questions :

1.  What is selective breeding?
Ans:  The process of selecting parents for obtaining special characters in their offspring, such as soft under hair in sheep is called selective breeding.

2.  Name different animals from which wool is obtained.
Ans:  Sheep, goat, yak, camel.

3.  Which is the most common silkworm used for obtaining silk.
Ans:  The most common silk moth is mulberry silk moth.

4.  The fleece of the sheep is mostly removed in hot weather. Give reason.
Ans:  Sheep hair is mostly removed in hot weather because it enables the sheep to survive without their protective coating in winter.

5.  Silk is obtained from silkworm but we find a wide variety of silk in the market. Give reason.
Ans:  This is because there are variety of silk moths looking very different from each other and yield different texture of silk yarn.

6.  How does the hair of certain animals help in keeping their bodies warm?
Ans:  Hair traps a lot of air and air being poor conductor of heat prevents heat loss from the body.

7.  Name the two fibres made up of proteins.
Ans:  Silk and wool are the two fibres made up of protein.

8.  Which stage in the life cycle of silk moth is called cocoon?
Ans:  The stage where caterpillars completely cover itself by silk fibres is called cocoon.