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What is wool for class 7?

4 Answer(s) Available
Answer # 1 #

Wool fibre is a highly organised structure whose main histological components include the cuticle, cortex and medulla. Wool fibre is a natural fibre and its characteristics such as diameter, crimps and length are essential parameters of the wool trait, as well as important indicators of the spinning efficiency of the wool.

The steps involved in wool production are as follows.

Wool fibres are obtained from sheep, goat, angora rabbits, goats, alpaca and even camels.

A summary of the conversion of fleece into wool fabrics is shown below.

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Dharam Sondhi
BAGGAGE HANDLER
Answer # 2 #

Wool is a textile fibr obtained from sheep and some other animals, including cashmere and mohair from goats, qiviut from muskoxen, angora from rabbits, and other types of wool from camelids.

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Liliane Fawcett
Photojournalist
Answer # 3 #
  • In making of blankets.
  • Carpets are made using wool.
  • Upholstery is made from wool.
  • Different types of insulations are made using wool.
  • Winter clothes are made from wool.
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Vara Rampal
CASKET ASSEMBLER METAL
Answer # 4 #

Question 1 Name two fibres obtained from animals?

Question 2 Describe how wool is obtained from sheep and processed to make woollen yarn?

Question 3 What is meant by shearing?

Question 4 What is meant by scouring?

Question 5 What is meant by sorting?

Question 6 In what type of weather shearing of sheep is done?

Question 7 Why does shearing not hurt the sheep?

Question 8 What type of feed is given to sheep?

Question 9 What is meant by shearing and breeding of sheep?

Question 10 Why do wool yielding animals have a thick coat of hair on their body?

Question 11 Why woollen garments keep us warm in winters?

Question 12 What is occupational hazard ? Name one occupational hazard?

Question 13 Where are Angora goats found in our country?

Question 14 Which animal produces wool for making fine Pashmina shawls?

☛ Also Read NCERT Solutions for Chapter 3 Fibre to Fabric

Natural fibres are threads obtained from plants and animals. Cotton, flax and jute are all plant fibres.

1 Wool 2 Silk

Wool comes from animals such as sheep, goat and yak, etc., whereas silk comes from silkworms.

Wool

Wool is the most commonly used animal fibre. Wool is the soft, wavy (or curly) hair which covers the body of a sheep. Wool is a modified form of hair that grows with a waviness. Because of the waviness of wool, the woollen fabrics have a greater bulk (than cotton fabrics) and hence trap more air. Due to this, woollen fabrics keep us more warm during cold, winter days.

Wool is obtained from the fleece (or hair) of sheep. Sheep grow wool on their body and once a year, this wool is sheared (cut off). Though wool comes mainly from sheep, some other animals also give us wool.

Wool comes from the animals like sheep, goat, yak, camel, Liama and alpaca.

The wool yielding animals have a thick coat of hair on their body to keep them warm during cold winter season. The hair (or wool) trap a lot of air. Air is a poor conductor of heat. So, the air trapped in hair (or wool) of these animals prevents their body heat from being lost to cold surroundings and keeps them warm in winter.

The hair (or wool) of these animals is removed only once in a year at the beginning of summer season. They can survive in hot weather without hair. And by the time winter comes, the thick hair(or wool) grows again on the body of these animals.

The hairy skin of sheep has two types of fibres that form its fleece (or wool coat):

(i)  the coarse beard hair, and

(ii) the fine, soft under-hair, close to the skin.

The fine hair provide the fibres for making wool.

The process of selecting parent sheep for obtaining special characteristics in their offspring (such as soft under-hair) is called ‘selective breeding‘.

The natural colour of wool is generally creamy white though some breeds of sheep produce wool having brown and black colours.

The under-fur of Kashmiri goat is soft. It is woven into fine shawls called Pashmina Shawls. Angora wool is obtained from Angora goats which are found in the hilly regions such as Jammu and Kashmir.

Yak wool is common in the hilly regions of Tibet and Ladakh.

Rearing of sheep means to look after the sheep by providing them feed (food), shelter and health care.

The persons who look after the sheep are called shepherds.

Sheep are herbivores and prefer to eat grass and leaves. So, shepherds take the herds of sheep to countryside for grazing. Apart from grazing grass, the sheep are also fed mixture of pulses, corn, jowar, oil cakes (oil cake is the material left after the extraction of oil from oil-seeds), and minerals. In winter, sheep are kept indoors and fed on leaves, grains and dry fodder.

Certain breeds of sheep have a thick coat of hair on their body which yields good quality wool in large quantities. The breeding of sheep is done to obtain such breeds of sheep which yield good quality wool in large quantities. This raises the quality and quantity of wool produced.

The cut off wool coat’ of a sheep (along with a thin layer of skin) is called fleece. The fleece consists of soft woollen fibres. The fleece of sheep is usually kept in one piece.

The yarn which we use for knitting sweaters or weaving shawls, etc. is called wool. Wool is obtained from the sheep by a long process which involves the following steps: Shearing, Scouring, Sorting. Dyeing, Combing and Spinning.

The hair of sheep along with a thin layer of skin (called fleece) are removed from the body of sheep. The process of removing hair (or cutting off hair) from the body of a sheep in the form of fleece is called shearing. The hair of sheep are cut off by using a cutting machine.

Shearing does not hurt the sheep because the uppermost layer of the skin of sheep is “dead. The shearing (cutting the hair) of sheep is done in the hot weather of summer so that sheep may survive without their protective coat of hair. The hair of sheep grow again before the onset of winter and protect them in cold weather. The fleece (or hair) of sheep provide woollen fibres. Woollen fibres are then processed to obtain woollen yarn.

The fleece of sheep (or cut hair of sheep) contain dust, dirt, dried sweat and grease, etc. The fleece (or sheared hair) of sheep is thoroughly cleaned by washing with soap (or detergent) and a lot of water in tanks.

The process of washing the fleece (cut hair of sheep) that removes dust, dirt, dried sweat and grease is called scouring. Scouring makes the fleece of sheep clean. The scoured fleece (or washed fleece) is then dried.

The wool is not uniform in all the parts of fleece of a sheep. Some parts of fleece have fine wool fibres whereas others have coarse wool fibres. Some parts of fleece have long wool fibres whereas others have short wool fibres. In sorting, the fleece is sent to a factory where it is broken and separated into sections of different quality fibres.

The process of separating the fleece of a sheep into sections according to the quality of woollen fibres is called sorting. The same quality wool obtained from the fleece of large number of sheep are then mixed together.

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.

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 and also removes the small fluffy fibres (called ‘burrs) which may be caught in them.

The long woollen fibres are spun (or twisted) into thick yarn called wool. The short woollen fibres are spun into fine yarn and then woven on a loom to make woollen cloth (like shawls, etc.). The quality of woollen cloth depends on the breed of sheep from which wool is obtained.

The people who do the job of sorting (separating) the fleece of sheep into fibres of different qualities are called sorter’s.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. Sorter’s disease is an occupational hazard.

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Panchito Uzuner
Novelist