3 FIBRE TO FABRIC TEXTBOOK QUESTIONS AND THEIR ANSWERS Q. (i) Why it hurts when someone pulls your hair but not when you go for a hair cut? Ans. It hurts when someone pulls our hair because the hair at the joint of the skin is being pulled whereas it does not hurt during hair cut because the hair joining the skin is not being pulled and the upper most layer of the skin is dead. (ii) Why a cotton garment cannot keep us a warm in winter as a woollen sweater does? Ans. Cotton garments allow the air (a poor conductor of heat) to pass through them and hence, this cannot keep us warm during winter. On the other hand, a woollen sweater trap a lot of air and thus, does not allow the heat from our body to go out. For this reason, woollen sweaters keep us warm during winters. Q.2. Are cotton thread and silk thread spun and woven in the same manner? 1
Ans. Yes, to some extent cotton threads and silk threads are spun and woven in the same manner. Q.3. You must be familiar with the following nursery rhymes : (i) Baa baa black sheep, have you any wool. (ii) Mary had a little lamb, whose fleece was white as snow. Answer the following : (a) Which parts of the black sheep have wool? (b) What is meant by white fleece of the lamb? Ans. (a) Wool from the black sheep is obtained from the (i) coarse beard hair, and (ii) the fine soft under hair close to the skin. (b) White fleece of the lamb means white hair of the lamb. Q.4. The silkworm is (a) a caterpillar, (b) a larva. Choose the correct option. (i) a (ii) b (iii) both a and b (iv) neither a nor b. Ans. Both a and b. 2
Q.5. Which of the following does not yield wool? (i) yak (ii) camel (iii) goat (iv) woolly dog. Ans. (iv) Woolly dog. Q.6. What is meant by the following terms? (i) Rearing (ii) Shearing (iii) Sericulture. Ans. (i) Rearing - Rearing of animals means taking care of economically useful animals by managing their breeding, feeding, medical care etc. for obtaining one or more of their product useful for human beings. (ii) Shearing The process of removal of fleece of animals such as sheep etc. along with a thin layer of skin is called shearing. (iii) Sericulture The rearing of silkworms for obtaining silk is called sericulture. Q.7. Given below is a sequence of steps in the processing of wool. Which are the missing steps? Add them. Shearing,, sorting,,. Ans. Shearing, scouring, sorting, dyeing, spinning. 3
Q.8. Make sketches of the two stages in the life history of the silkmoth which are directly related to the production of silk. Ans. Q.9. Out of the following, which are the two terms related to silk production? Sericulture, Floriculture, Moriculture, Apiculture, Silviculture. Ans. (i) Sericulture and (ii) Moriculture. (i) Silk production involves cultivation of mulberry leaves and rearing silkworms. (ii) Scientific name of mulberry is Morus alba. Q.10. Match the words of Column I with those given in Column II: 4
Column I Column II 1. Scouring (a) Yields silk fibres 2. Mulberry leaves (b) Wool yielding animal 3. Yak (c) Food of silk worm 4. Cocoon (d) Reeling (e) Cleaning sheared skin Ans. Column I Column II 1. Scouring (e) Cleaning sheared skin 2. Mulberry leaves (c) Food of silk worm 3. Yak (b) Wool yielding animal 4. Cocoon (a) Yields silk fibres. Q.11. Given below is a cross word puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words. Down Across (D) 1 : Thorough washing (A) 1 : Keeps warm 5
2 : Animal fibre 2 : Its leaves are eaten by slik worms 3 : Long thread like structure 3 : Hatches from egg of moth Ans. D. 1 : Scour A. 1 : Wool 2 : Silk 2 : Mulberry 3 : Fibre 3 : Caterpillar 6