NCERT Class 7 Science Chapter 3 - Fibre to Fabrics

Chapter 3 - Fibre to Fabrics

Question 1: 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 the white fleece of the lamb?
Answer:
a) Wool is obtained from hairy fibres of the sheep.
b) White fleece of the lamb refers to the white colour of their fur.

Question 2: 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
Answer: (iii) both a and b

Question 3: Which of the following does not yield wool?
(i) Yak
(ii) Camel
(iii) Goat
(iv) Woolly dog
Answer: (iv) Woolly dog

Question 4:What is meant by the following terms? (i) Rearing (ii) Shearing (iii) Sericulture
Answer:
• Rearing: The process of keeping, feeding, breeding and medical care of useful animals is called rearing.
• Shearing: The process of removal of fleece of the sheep along with a thin layer of skin from its body its body is called shearing.
• Sericulture: The rearing of silkworm for obtaining silk is called sericulture.

Question 5: Given below is a sequence of steps in the processing of wool. Which are the missing steps? Add them.
Shearing, __________, sorting, __________, __________, __________.
Answer: Shearing, Scouring, Sorting, Picking of burrs, Dyeing of fibres, making of yarn.

Question 6: Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
Answer:

Question 7: Out of the following, which are the two terms related to silk production?
Sericulture, Floriculture, Moriculture, Apiculture and Silviculture
Hints: (i) Silk production involves cultivation of mulberry leaves and rearing silkworms.
(ii) Scientific name of mulberry is Morus Alba
Answer: Sericulture and Moriculture

Question 8: Match the words of Column I with those given in Column II:

Answer:

Question 9: Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down
1: Thorough washing
2: Animal fibre
3: Animal fibre
Across
1: Keeps warm
2: Its leaves are eaten by silkworms
3: Hatches from egg of moth

Answer: