NCERT Solutions for Class 7 Science - Fibre to Fabric

Q1: 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 the hairy fibres (hair) of the sheep. (b) White fleece of the lamb refers to the white coloured hair of the lamb.

Q2: 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

Q3: Which of the following does not yield wool? (i) Yak (ii) Camel (iii) Goat (iv) Woolly dog
Answer: (iv)Woolly dog

Q4: What is meant by the following terms? (i) Rearing (ii) Shearing (iii) Sericulture
Answer: (i) Rearing: Rearing means helping someone to grow up. (ii) Shearing: It is the process of removal of fleece along with a thin layer of skin from the body of sheep. (ii) Sericulture: Sericulture refers to the rearing of silkworms to obtain silk.

Q5: 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__, __dying of fibres__, making of yarn__

Q6: Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
Answer: 
The two stages in the life history of silk moth directly related to silk production are

Q7: 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

Q8: Match the words of Column I with those given in Column II:

Answer: 
(i) Scouring (e) Cleaning sheared skin
(ii) Mulberry leaves (c) Food of silk worm
(iii) Yak (b)  Wool yielding animal
(iv) Cocoon (a) Yields silk fibres

Q9:  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 Across (D) 1: Thorough washing (A) 1: Keeps warm
2: Animal fibre 2: Its leaves are eaten by silkworms
3: Long thread like structure 3: Hatches from egg of moth
Answer: