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NCERT Solutions for Class 7th Science Chapter 3 – Fibre to Fabric
National Council of Educational Research and Training (NCERT) Book Solutions for Class 7th
Chapter: Chapter 3 – Fibre to Fabric
Class 7th Science Chapter 3 Fibre to Fabric NCERT Solution is given below.
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 the hairy fibres (hair) of the sheep.
(b) White fleece of the lamb refers to the white coloured hair of the lamb.
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: (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.
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, dying 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: The two stages in the life history of silk moth directly related to silk production are
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
Match the words of Column I with those given in Column II:
|Column I||Column II|
|(i) Scouring||(a) Yields silk fibres|
|(ii) Mulberry leaves||(b) Wool yielding animal|
|(iii) Yak||(c) Food of silk worm|
|(iv) Cocoon||(d) Reeling|
|(e) Cleaning sheared skin|
|Column I||Column II|
|(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|
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.
(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
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