Fibre to fabric
Very Short Answer Type Questions
1. Name two fibres obtained from animals.
Ans: Silk and wool are the two fibres which obtained from animals .
2. Which type of wool is common in Tibet and Ladakh ?
Ans: Yak wool is common in Tibet and Ladakh .
3. Where are Angora goats found in our country ?
Ans: Angora goats are found in hilly regions such as Jammu and Kashmir .
4. Which animal produces wool for making fine Pashmina shawls ?
Ans: Kashmiri goat produces wool for making fine pashmina shawls .
5. Where are the wool-yielding animals called llama and alpaca found?
Ans: The wool-yielding animals called llama and alpaca found in South America .
6. Name any two breeds of sheep found in India.
Ans: Marwari and Pathan wasi these are two breeds of sheep found in india .
7. State whether sheep are herbivores or carnivores.
Ans: Sheep are herbivores because sheep eat only grass and green leafy vegetables .
8. What terms are used for the following processes ?
(a) Removing hair of sheep alongwith a thin layer of skin.
Ans: Shearing
(b) Washing of sheep's fleece to remove dust, dirt and grease.
Ans: Scouring
(c) Separating sheep's fleece into fibres of different qualities.
Ans: Sorting
9. What causes sorter's disease ?
Ans: The people who do the job of sorting (separating) the fleece of sheep into fibres of different qualities are called 'sorters'. The sorter's job is very risky because sometimes they get infected by the bacteria called 'anthrax' which cause a deadly blood disease called 'sorter's disease'.
10. Which step comes first in the production of woollen yarn from sheep: scouring or shearing ?
Ans: Shearing step comes first in the production of woollen yarn from sheep.
11. Name a natural fibre obtained from insects.
Ans: Silk is a natural fibre obtained from insect .
12. State whether the following statement is true or false :
The adult silk moth spins cocoons from which silk is obtained.
Ans: False .
Silkworms or the caterpillars spin cocoons .
13. Name the tree whose leaves provide food for the silkworms.
The mulberry tree whose leaves provide food for the silkworms .
14. What are the natural colours of the fleece of sheep and goats?
Ans: The natural colours of the fleece of sheep and goat creamy white though some breeds of sheep and goats have brown and black colour of wools .
15. Which stage comes earlier in the life history of a silk moth-pupa or larva ?
Ans: The larva stage comes before the pupa stage in the life cycle of a silk moth .
16. Which of the following actually makes the silk fibres ? Larva, Pupa, Adult silk moth
Ans: The larva makes the silk fibres .
17. Which of the following terms is related to silk production ?
Floriculture, Tissue culture, Silviculture, Apiculture, Sericulture
Ans: The term sericulture is related to silk production
18. Name two fibres which are made of proteins.
Ans: Wool and silk fibres are made of proteins .
19. State whether artificial silk is an animal fibre or a plant fibre.
Ans: Yes ! Artificial silk is a kind of plant fibre .
20. Fill in the following blanks with suitable words:
(a) The process of selecting parents for obtaining special characteristics in their offsprings is called selective breeding .
(b) Angora wool is obtained from Angora goats .
(c) Llama and alpaca also yield wool .
(d) Sheep are herbivores and prefer grass and leaves.
(e) Lohi and nali are breeds of sheep
(f) Silk is obtained from the cocoon of a silk moth.
(8) Silk fibres are made of a protein .
(h) Silkworms are larvae (plural form of larva) of silk moth.
(i) Silkworms spin cocoons of silk fibres
(j) The process of taking out threads from the cocoons for use as silk is called reeling the silk.
Short Answer Type Questions
21. What type of feed (or food) is given to sheep ?
Ans: Sheep are fed grass, leaves, mixture of pulses, corn, jowar, oil cake etc .
22. What is meant by the rearing' and 'breeding of sheep ?
Ans: Rearing and breading means to look after the sheep by providing them shelter and health care .
23. Name the various steps involved in the production of wool from sheep.
Ans: The various steps involved in the production of wool from sheep are
1. Shearing
2. Scouring
3. Sorting
4. Dyeing
5. Combing
6. Spinning
4.Why do wool-yielding animals (like sheep) have a thick coat of hair on their body?
Ans: Wool yielding animals like sheep have a thick coat of hair on their body to keep them warm during cold winter season .
25. Explain why, a woollen garment keeps us very warm in winter.
Ans: Woolen garments trap a lot of air .Air is a poor conductor of heat . So the air trapped in hair or wool of these animals prevent their body heat from being lost to cold surrounding and keeps them warm in winter .
26. What is an occupational hazard ? Name one occupational hazard.
Ans: The sorter's job is very risky because sometimes they get infected by the bacteria called 'anthrax' which cause a deadly blood disease called 'sorter's disease'. The risks faced by people working in any industry due to the "nature of their work are called occupational hazards. Sorter's disease is an occupational hazard.
27. What is meant by the term 'sericulture?
Ans: The rearing of silkworms for obtaining silk is called sericulture .
Sericulture means silk farming .
28. Name the most common silk moth. What are the characteristics of silk
Ans: The most common silkmoth is silkworm .
The silk is soft, lustrous (shiny), elastic .
29. How will you distinguish between natural silk and artificial silk ?
Ans: Natural silk is obtained from the cocoons of silkworms and it is made of a 'protein'. Natural silk is an animal fibre.
Artificial silk (called rayon) is obtained from wood pulp and it is made of modified plant material 'cellulose' (Paper is also made of cellulose obtained from wood pulp).
We can also distinguish between natural silk (or pure silk) and artificial silk by performing the 'burning tesť.
natural silk fabric and another piece of artificial silk fabric, burn them separately and observe the smell produced :
The fabric which burns giving a smell of burning hair will be natural silk (or pure silk), (in The fabric which burns giving a smell of burning paper will be artificial silk (or rayon). Just like silk, wool is also made of proteins. So, a piece of wool (or woollen fabric) also burns giving the smell of burning hair.
30. What is meant by the term 'reeling the silk' ? How is it done?
Ans: The process of taking out silk fibres from the cocoons is called reeling.
This is done as follows:
First all the cocoons are collected .The pile of cocoons is placed in hot water. Hot water makes the silk fibres of cocoons to separate out. The long silk fibres are obtained by unwinding the threads from cocoons.
31. Match the words of column I with those given in column 11
Column 1 Column 2
(1)Scouring - Cleaning shared wool
(2) Mulberry leaves- Food of silkworm
(3) Yak - Wool yielding animal
(iv) Cocoon - Reeling
32. Name any five animals which yield wool. Which is the most common type of wool available in the market?
Ans: Five wil yielding animals are sheep , goat , yak , camel , allama and alpana .
Wool obtained from sheep is commonly available in the market .
33. Name any four types of silk. State whether silk is an animal fibre or a plant fibre
Ans: Mulberry silk, Tadar silk, Moga silk and kosa silk
These all are obtained from the cocoons spun by the silkworms of different types of silk moth .
So these all are animal silk .
34. What is a cocoon ? Name the fibre of which a cocoon is made
Ans: Thy silky covering spun by the silkworm or caterpillar is called cocoon.
A cocoon is made of silk fibre secreted by silkworm.
35. Arrange the following steps in the correct order in which they are carried out during the production of woollen yarn from the sheep: Combing. Shearing, Dyeing, Scouring. Spinning. Sorting
Ans : In correct order the steps are
1. Shearing
2. Scouring
3. Sorting
4. Dyeing
5. Combing
6. Spinning
Long Answer Type Questions
36. Describe briefly, how wool is obtained from sheep and processed to make woollen yarn
Ans: Wool comes mainly from sheep. In order to obtain wool, sheep are reared and bred their hair is cut and processed into wool.
Rearing and Breeding of Sheep :
Rearing of sheep means to look after the sheep by providing them feed (food), shelter and health care.
The breeding of sheep is done to obtain such breeds of sheep which yield good quality of wool . Such sheep are selectively bred by choosing atleast one parent sheep of good breed .
Obtaining of wool :
Wool is obtained from the sheep by a long process which involves the following steps :-
(i) Shearing
The hair of sheep alongwith a thin layer of skin (called fleece) are removed from the body of a sheep in the form of fleece .
(ii) Scouring
The fleece of sheep (or cut hair of sheep) contain dust, dirt, dried sweat and grease, etc. So, the fleece must be cleaned before it can be processed into wool yarn .
(iii) Sorting
In sorting the fleece is sent to a factory where it is broken and sections according to the different quality of woollen fibres (such as fine, coarse, long short, etc) .
(iv) Dyeing
The natural fleece or hair of sheep (or goats) is white, brown or black in colour. The white woollen fibres obtained by sorting can be dyed in different colours.
(V) Combing
Combing is a method to prepare woollen fibres for spinning the yarn. This is done by using combs having metal teeth. The process of combing straightens the entangled woollen fibres .
(VI) Spinning
The long woollen fibres are spun (or twisted) into thick yarn called 'wool' (which is used for knitting sweaters, etc.). The short woollen fibres are spun into fine yarn and then woven on a loom to make woollen cloth (like shawls, etc) .
From the above discussion we conclude that the sheep's hair is sheared off from the body, scoured, sorted, dyed, combed and spun to obtain wool (for knitting sweaters) and woollen yarn (for weaving woollen cloth).
37. What is meant by the following terms?
(a) Shearing
The process of removing hair (or cutting off hair) from the body of a sheep in the form of fleece is called shearing
(b) Scouring
The process of washing the fleece (cut hair of sheep) that removes dust, dirt, dried sweat and grease is called scouring
(c) Sorting
The process of separatingthe felece of a sheep into section according their qualities of fibre is called sorting .
38. Describe the life history of silk moth briefly. Make sketches of the two stages in the life history of silk moth which are directly related to the production of silk.
Ans: Silk moth is a kind of insert which resembles a butterfly . The life history of silk moth is interesting because silk moth is not formed from the eggs directly .
We can describe the life history of silk moth as follows.
The female silk moth lays eggs on the leaves of a tree such as mulberry tree .
The eggs hatch to form worm-like larvae .The larvae of silk moth are called caterpillars' or silkworms.
The silkworms feed on the leaves of mulberry tree and grow bigger in size, Silk is formed in liquid form in the two glands in the silkworms head.
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