NCERT Solutions for Chapter 3 Fibre to Fabric Class 7 Science
Book Solutions1
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) The hairy skin i.e. fleece of the black sheep have wool.
(b) White fleece means the white coloured hair of the lamb.
Exercises
Page Number 32
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
(i) a
(ii) b
(iii) both a and b
(iv) neither a nor b
Answer
(iii) both a and b
Exercises
Page Number 32
3
Which of the following does not yield wool?
(i) Yak
(ii) Camel
(iii) Goat
(iv) Woolly dog
(i) Yak
(ii) Camel
(iii) Goat
(iv) Woolly dog
Answer
(iv) Woolly dog
Exercises
Page Number 32
4
What is meant by the following terms?
(i) Rearing
(ii) Shearing
(iii) Sericulture
(i) Rearing
(ii) Shearing
(iii) Sericulture
Answer
(i) Rearing : It means taking care of herds of animals which includes feeding, grazing, breeding, etc. for economical purpose like meat and other useful products.
(ii) Shearing : The removal of fleece of the sheep along with a thin layer of skin from its body is called shearing.
(iii) Sericulture : The rearing of silkworms to obtain silk economically is called sericulture.
Exercises
Page Number 32
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, burrs picking, dying, rolling
Exercises
Page Number 32
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 the silk moth which are directly related to the production of silk:
Spinning of cocoon of silk threads around caterpillar.
Changing of caterpillar into pupa.
Exercises
Page Number 32
7
Out of the following, which are the two terms related to silk production?
Sericulture, floriculture, moriculture, apiculture and silviculture.
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.
(ii) Scientific name of mulberry is Morus alba.
Answer
Sericulture and moricultur
Exercises
Page Number 32
8
Match the words of Column I with those given in Column II:
|
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 |
Answer
|
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 |
Exercises
Page Number 32
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
(D) 1 : Thorough washing
2 : Animal fibre
3 : Long thread like structure
2 : Animal fibre
3 : Long thread like structure
Across
(A) 1 : Keeps warm
2 : Its leaves are eaten by silkworms
3 : Hatches from egg of moth
2 : Its leaves are eaten by silkworms
3 : Hatches from egg of moth
Answer
Exercises
Page Number 33