Q3Short answer
Fibre to Fabric
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(a)
Chapter 3 – Fibre To Fabric
Class 7 Science · 23 questions · 23 with answers
Questions
Q4Multiple choice
Silk fibre is obtained from
- (a)fleece of sheep
- (b)cotton ball
- (c)cocoon
- (d)shiny jute stalk
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(c) cocoon
Q5Multiple choice
Wool fibre cannot be obtained from which of the following?
- (a)Goat
- (b)Llama
- (c)Alpaca
- (d)Moth
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(d) Moth
Q6Multiple choice
Selective breeding is a process of
- (a)selecting the offsprings with desired properties.
- (b)selecting the parents with desired properties.
- (c)selecting an area for breeding.
- (d)selecting fine hair for good quality wool.
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(b) selecting the parents with desired properties.
Q7Multiple choice
The general process that takes place at a sheep shearing shed is
- (a)removal of fleece.
- (b)separating hair of different textures.
- (c)washing of sheep fibre to remove grease.
- (d)rolling of sheep fibre into yarn.
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(a) removal of fleece.
Q8Multiple choice
The term sericulture is used for
- (a)culture of bacteria.
- (b)rearing of silkworm.
- (c)making silk fabric from silk yarn.
- (d)production of sarees.
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(b) rearing of silkworm.
Q9Multiple choice
Reeling of silk is
- (a)a process of making silk reels.
- (b)spinning of silk fibres.
- (c)weaving of silk cloth.
- (d)the process of taking silk threads from cocoon.
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(d) the process of taking silk threads from cocoon.
Q10Multiple choice
Silkworms secrete fibre made of
- (a)fat
- (b)cellulose
- (c)protein
- (d)nylon
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(c) protein
Q11Multiple choice
Fill in the blanks in the following statements.
- (a)_________ and _________ fibres are obtained from animals.
- (b)Silk fibres come from _________ of silk _________.
- (c)Wool yielding animals bear _________ on their body.
- (d)Hair trap a lot of _________, which is a poor _________ of heat. FIBRE TO FABRIC 17
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(a) _________ and _________ fibres are obtained from animals.
(b) Silk fibres come from _________ of silk _________.
(c) Wool yielding animals bear _________ on their body.
(d) Hair trap a lot of _________, which is a poor _________ of heat. FIBRE TO FABRIC 17
Q12Multiple choice
State whether the following statements are True or False. If false, correct them.
- (a)Silkworms are caterpillars of silk moth.
- (b)In India, camels and goats are generally reared for obtaining wool.
- (c)The rearing of silkworms for obtaining silk is called silviculture.
- (d)In the process of obtaining wool from fleece, sorting is done after scouring. (e) Yak hair are not used to make woollen fabric.
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(a) Silkworms are caterpillars of silk moth.
(b) In India, camels and goats are generally reared for obtaining wool.
(c) The rearing of silkworms for obtaining silk is called silviculture.
(d) In the process of obtaining wool from fleece, sorting is done after scouring. (e) Yak hair are not used to make woollen fabric.
Q13Very short answer
How do the hair of certain animals help in keeping their bodies warm?
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Hair traps a lot of air, which is a poor conductor of heat. SHORT ANSWER QUESTIONS
Q14Match the following
Match the items of Column I with the items given in Column II.
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(a) (iii); (b) (iv); (c) (ii); (d) (i)
Q15Multiple choice
Various steps involved to obtain wool from fleece are given here.
- (i)Picking out the burrs
- (ii)Dyeing in various colours
- (iii)Shearing
- (iv)Scouring (v) Sorting Write the above steps in the correct sequence in which they are carried out.
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(iii) Shearing
(iv) Scouring (v) Sorting Write the above steps in the correct sequence in which they are carried out.
(i) Picking out the burrs
(ii) Dyeing in various colours
Q16Multiple choice
Some words related with silk are jumbled up. Write them in their correct form.
- (a)TURECULRISE
- (b)WILSMORK
- (c)BELMURRY
- (d)RINGLEE
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(a) TURECULRISE
(b) WILSMORK
(c) BELMURRY
(d) RINGLEE
Q17Short answer
Figure 3.1 shows three rings of circles with letters in them. Some of these letters in each ring can form the name of one wool yielding animal. Find the names of these animals. Fig. 3.1
This question refers to a figure in the original PDF.
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Yak, Camel, Sheep
Q18Multiple choice
Write a caption for each of the figures given as Figure 3.2 (a–d).
This question refers to a figure in the original PDF.
- (a)
- (b)FIBRE TO FABRIC 19
- (c)
- (d)Fig. 3.2
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(a)
(b) FIBRE TO FABRIC 19
(c)
(d) Fig. 3.2
Q19Multiple choice
Steps for the production of silk are given below in a jumbled order. Arrange them in their proper sequence.
- (a)Eggs are warmed to a suitable temperature for the larvae to hatch from eggs.
- (b)Fibers are taken out from the cocoon.
- (c)After 25 to 30 days, the caterpillars stop eating and start spinning cocoons.
- (d)The larvae/caterpillars or silkworms are kept in clean trays along with freshly chopped mulberry leaves. (e) Female silk moths lay eggs. (f) Cocoons are kept under the sun or boiled in water.
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(a) Eggs are warmed to a suitable temperature for the larvae to hatch from eggs.
(d) The larvae/caterpillars or silkworms are kept in clean trays along with freshly chopped mulberry leaves. (e) Female silk moths lay eggs. (f) Cocoons are kept under the sun or boiled in water.
(c) After 25 to 30 days, the caterpillars stop eating and start spinning cocoons.
(b) Fibers are taken out from the cocoon.
Q20Match the following
A wholesale woollen fibre dealer gets the woollen fibre of different textures sorted for various purposes. Match the items in Column I with the woollen fibre in Column II.
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(a) (iii); (b) (i); (c) (ii); (d) (iv) LONG ANSWER QUESTIONS
Q21Fill in the blanks
Complete the paragraph related to the life history of silk moth by filling in the blanks. The ____(a)___ silk moth lays ___(b)___, from which hatch ____(c)___ called ___(d)____ or ___(e)____. They grow in size and when the caterpillar is ready to enter the next stage of its life history called ___(f)____, it first weaves a covering to hold itself, which is known as ___(g)____.
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(a) female (b) eggs (c) larvae (d) caterpillars (e) silkworms (f) pupa (g) cocoon
Q22Long answer
Paheli went to the market to buy sarees for her mother. She took out a thread from the edge of the two sarees shown by the shopkeeper and burnt them. One thread burnt with a smell of burning hair and the other burnt with the smell of burning paper. Which thread is from a pure cotton saree and which one from a pure silk saree? Give reason for your answer.
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The thread which burns with a smell of burning hair is from pure silk. Silk and hair are protein fibres. Cotton and paper both are carbohydrates, and on burning they give similar smell.
Q23Long answer
Explain the phrase – “Unity is Strength” on the basis of the making of fabric from fibre.
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Hint: Fabric needs more energy to tear apart as compared to a single fibre.
Q24Long answer
Write various steps for processing fibres into wool.
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Hint: Write briefly about (i) shearing, (ii) scouring, (iii) sorting (iv) picking out of burrs from the hair, (v) dyeing of fibres, (vi) straightening, combing of fibres and rolling into yarm.
Q25Long answer
Describe the life history of silk moth with the help of figures of various stages. ACIDS, BASES AND SALTS 31
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Hint: Trace life history of silk moth from eggs – larvae – pupa – moth (Fig. 3.9 a – f of Class VII Science Textbook, NCERT) ANSWERS 105