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NCERT 6TH CLASS SCIENCE CHAPTER FIBER TO FABRIC

INTRODUCTION
Any fabric (cloth) is made up of yarns arranged together which are further made up of still thinner strands called fibres. Thread like part in animal and vegetable tissues is called fibres. They are the raw materials that are long, strong and pliable enough to be spun into yarns and woven into fabrics. 
 
CLASSIFICATION OF FIBRES 
Natural, semi-synthetic and artificial (synthetic) fibres. 
(A) Natural Fibres : 
Fibres obtained from plants are called plant fibres and fibres obtained from animals are called animal fibres. Plant and animal fibres together are called natural fibres. For example cotton, jute and silk. 
The Fibres of some fabrics such as cotton, jute, silk and wool are obtained from plants. Wool and silk fibres are obtained from animals. Wool is obtained from the fleece of sheep or goat. It is also obtained from the hair of rabbits. yak and camels, Silk fibre is drawn from the cocoon of silkworm.
 
(i) Cotton : It is cultivated where warm and sunny weather stays for at least half of the year. Cotton plants require warm temperature ranging between 21° C to 27°C with sunny and dry weather. By the time of harvesting rainfall between 50 cm to 80 cm is another conducive condition for its growth. Black soil, which has the ability to retain moisture is best suited for cotton cultivation. The fruits of the cotton plant (Cotton bolls) are about the size of a lemon. After maturing, the bolls burst open and the seeds covered with cotton fibres. Cotton is usually picked by hand. Fibres are then separated from the seeds by combining. This process is called ginning of cotton. Ginning was traditionally done by hand. These days Machines are also used for ginning.
 
(a) Cotton plants (b) cotton balls
• Cotton is used in the manufacture of fish nets, coffee filters, tents and in book binding. 
• The cottonseed, which remains after the cotton is separated from its seeds or ginned, is used to produce cotton seed oil, which after refining can be consumed like any other vegetable oil. 
• The cotton seed meal (khal) that is left is generally fed to livestock. 
• In India, main cotton producing states are Maharashtra, Haryana, Andhra Pradesh, Punjab and Gujarat. Sourthern United states, China and India are the largest producer of cotton. 
 
(ii) Jute: It is a long, soft, shiny plant and Is one of the cheapest natural fibres. Jute fibres are composed of cellulose and lignin. 
Jute is a rainy season crop, grown best in warm, humid climate.Jute plant requires temperature ranging from 17°C to 40°C and rain fall from 120 mm to 150 mm 
Almost 85% of the world's jute CUltivation is concentrated in deltas of Ganga 
Harvesting of jute plant is done at flowering state. The stalks are cut close to the ground. They are then tied into bundles and soaked in water for 20 days. It softens the tissues and permits the fibres to be separated, The fibres are then stopped from the stalks in long strands and washed in clear, running water. Then they are spread on a that ched roof to dry. 
Jute is said to have more than a thousand uses. It is the second most important vegetable fibre after cotton; not only for its wider cultivation. but also for its uses. 
 
• Jute is used to make cloth for wrapping bales of raw known as Bombyx mori, which feeds on mulberry cotton, and to make sacks and coarse cloth. Jute leaves. Female moth lays eggs , which hatch larvae fibres are also woven into curtains, chair coverings, after 20 days. The larvae make their cocoons by using bags, carpets, hessian cloth , etc. 
• In india, jute is produced
...
West Bengal, Meghalaya, Bihar, Orissa and Assam.
 
KNNITING: 
In knitting, a single yarn is used to make a piece of fabric.
SPINNING : 
The Process of making yarn from fibres is called spinning. In this process, fibres from a mass of cotton wool are drawn out and twisted. This brings the fibres together to form a yarn.
WEAVING :
The process of arranged two sets of yarns together to make a fabric is called weaving. 
 
(iii) Wool : It is a fibre obtained from animals like sheep, lambs and goats. It is a form of hair, with a wavy structure characteristic of the breed of sheep comes from sheep, llama, alpaca, guanaco and vicuna. In India, mostly sheep are reared (to bring up) for getting wool. Sheep hair is sheared off from the body, scoured, sorted, dried, dyed, spun and woven to yield wool. 
Shearing: The fleece of the sheep along with a thin layer of skin is removed from Its body. This is called shearing. 
Scouring :The sheared skin with hair is thoroughly washed In tanks to remove grease, dust and dirt. This is called scouring. 
Sorting : Separation of hair of different textures is called sorting. 
Fibres can be dyed in various colours, as the natural fleece (hair) of sheep and goats is black brown or white. 
The longer fibres are made into wool for sweaters and shorter fibres are spun and woven into woolen clothes. 
Wool, spun from the fleece of sheep, is versatile, durable and elastic. 
Angora wools Is obtained from angora goats, which are found in hilly areas like Jammu and Kashmir. 
Yak wool is commonly found in areas like Laddakh and Tibet. 
Wool obtained from Kashmir goat is soft and is used to weave fine quality shawls called Pashmina shawls. 
Wool is also obtained from fur (hair) on the body of camels. It is used making carpet etc. 
Llama and Alpaca. found in South America, also yield wool. 
Wool is used for making coats, suits , shawls, scarves, gloves and carpets. It traps air and so it has insulating properties. 
While sorting wool, workers (sorters) get infected by bacterium, anthrax, which causes fatal blood disease called sorter's disease. Such risks faced by workers in any industry are called occupational hazards. 
(iv) Silk: It is a natural fibre consisting mainly of two proteins, fibroin and sericin. 
• Silk fibre is produced from a silkworm or silk moth the wet sticky substance produced by the silk glands. The cocoon is spun using two threads from the two glands, in a figure of eight , around Itself and changes into a pupa. The cocoons are either roasted or dropped in balling water to kill the pupa. This releases the silk threads from the cocoon, which are then spun into a reel. 
The science related to silk production is called sericulture. 
Silk is considered the queen of fibres. It is used for making dress materials, saris, scarves, jackets. gloves and carpets. 
The damaged or waste cocoons are used to produce an inferior quality of silk called spun silk. 
Crepe is a kind of silk thread made by twisting individual threads of raw silk, then doubling two or more of these together and twisting them again. 
Tram is the type of silk thread made by twisting two or more silk threads together in only one direction. 
Thrown sIngles is the type of silk, in which individual threads are twisted in only one direction. 
Organizing is the type of silk thread made by twisting a thread in one direction bringing two or more such threads together and twisting them in the opposite direction . 
Mulberry silk is produced by Bombyx mori worms. These worms are fed on the leaves of mulberry trees. 
 
(B) Semi-synthetic fibres: 
These are obtained from naturally occurring fibres oy chemical modifications. For example, cellulose on reaction with acetic anhydride In the presence of concentrated sulphuriC acid gives cellulose dlacetate, which is used for making threads of acetate and other materials like films and glasses. 
 
(C) Synthetic (artificIal) fibres: 
Synthetic fibres are manufactured by man in the laboratories. For example: nylon, acrylic and polyester. 
 
OBJECTIVE QUESTIONS
1. Eri is a type of 
(A) silk (B) wool 
(C) cotton (D) None of these 
2. Jute is obtained from which part of patsun ? 
(A) leaves 
(B) Root 
(C) Stem 
(D) Both leaves and stem. 
3. Wool burns with smell of burning hairs 
(A) as it is obtained from hairs of sheep and goat. 
(B) because it is a natural fibre. 
(C) because it is synthetic fibre. 
(D) None of these 
4. Pashmina shawls are obtained from the skin of which animal ? 
(A) Kashmiri Goat (B) Camel 
(C) Yak (D) None of these 
5. Which materials were used for clothes in 
ancient times? 
(A) Animal skins (B) Grass 
(C) Vines (D) All of these 
6. Which among these bodies or organisations produce high quality wool ? 
(A) International wool supply 
(B) International wool secretariat 
(C) Indian wool status 
(D) None of these 
7. Wool is a/ an
(A) fibre obtained from cocoon. 
(B) artificial fibre 
(C) animal fibre 
(D) plant fibre 
8. The stage in life cycle of an insect excludes 
(A) pupa (B) caterpillar 
(C) sericulture (D) None of these 
9. The disease most common among the 
workers of sericulture industry is 
(A) respiratory and skin diseases 
(B) cancer 
(C) tuberculosis 
(D) low and high blood pressure 
10. The fabric made from the used wool, by 
carding and spinning is called 
(A) shoddy (B) kemp 
(C) coarse wool (D) fleece 
11. While bursting crackers it is safe to wear clothes made of 
(A) nylon (B) polyesters 
(C) cotton (D) silk 
12. Wool is soluble in 
(A) alcohols 
(B) aldehydes 
(C) acids and bases both 
(D) None of these 
13. Which of the following is a natural polymer? 
(A) Cellulose (B) Nylon 
(C) Polythene (D) PVC 
14. Process of removing hairs of a sheep is called 
(A) Weaving (B) Shearing 
(C) Spinning (D) Ginning 
15. Yak wool is obtained in 
(A) Kerela (B) Uttar Pradesh 
(C) Madhya Pradesh (D) ladakh 
16. Woolen clothes keep us warm as 
(A) wool is an animal fibre. 
(B) wool is made up of proteins. 
(C) wool traps air and air is a good conductor of heat. 
(D) wool traps air and air Is a poor conductor of heat. 
17. The fibres of silk are made up of 
(A) fat (B) protein 
(C) carbohydrate (D) vitamin 
18. The process of making yarns from fibres is known as 
(A) bailing (B) spinning 
(C) reeling (D) ginning
 
SUBJECTIVE QUESTIONS
1. Why a cotton garment cannot keep us as warm in winter as a woollen sweater can ? 
2. Name any four wool-yielding animals. 
3. Match the items of column 'A' and column 'B' Column 'A' Column 'B' 
(i) Cocoon (a) Wool 
(ii) Science of rearing silk (b) Yields silk 
fibres. worms so as to obtain silk. 
(iii) Australia (c) Sericulture 
(iv) China (d) Silk 
4. Explain the following terms. 
(i) Shearing  (ii) Scouring  (iii) Sorting 
 
ANSWER KEY
1. A 2. C 3. A 4. A
5. D 6. B 7. C 8. C
9. A 10. A 11. C 12. C
13. A 14. B 15. D 16. D
17. B 18. B
 
MULTIPLE CHOICE QUESTIONS
1. Paheli wants to present her friend a gift made of plant-fibre. Which out of the following will she select?
(a) Jute bag (b) Woollen shawl (c) Silk saree (d) Nylon scarf
 
2. Which statement out of the following is incorrect?
(a) Use of Charkha was popularised by Mahatma Gandhi as a part of the Independence Movement.
(b) In India, jute is mainly grown in Kerala and Punjab.
(c) To make fabric, the fibres are first converted into yarns.
(d) Sufi saint Kabir was a weaver.
 
3. Which of the following materials did people use in ancient times for making clothes?
(i) Leaves of trees (ii) Newspaper
(iii) Metal foils (iv) Animal skins and furs
(a) (i) and (ii) (b) (i) and (iii)
(c) (ii) and (iii) (d) (i) and (iv)
 
4. Which of the following is not a natural fibre?
(a) Cotton (b) Jute (c) Nylon (d) Flax
 
5. Which set of substances is not used for making fibres?
(a) Silk, chemicals (b) Yak hair, camel hair
(c) Husk, bones (d) Flax, wool
 
6. Boojho went to a cloth shop. There he found a fabric which was smooth to touch, had vibrant colour and shine. The fabric could be
(a) Cotton (b) Wool (c) Silk (d) Jute
 
7. Which part of the jute plant is used for getting jute fibre?
(a) Flower (b) Stem (c) Fruit (d) Leaf
 
8. Yarn is woven to get fabric using
(a) charkha (b) spinning machines
(c) looms (d) knitting needles
 
9. Beera is a farmer. His field has black soil and the climate is warm. Which fibre yielding plant should he grow in his field?
(a) Jute (b) Cotton (c) Coconut (d) Wool
 
10. The correct sequence to get cloth is :
(a) fibre ? fabric ? yarn (b) fibre ? yarn ? fabric
(c) fabric ? yarn ? fibre (d) yarn ? fibre ? fabric
 
11. Boojho wants to make yarn from fibre at home. Which of the following will he use to carry out the task?
(a) Powerloom (b) Handloom (c) Charkha (d) Knitting needles
 
VERY SHORT ANSWER QUESTIONS
 
12. Yarn, fabric and fibres are related to each other. Show the relationship by filling the blanks in the following sentence.
Fabric of cotton saree is made by weaving cotton_ _ _ _ _ _which in turn is made by spinning thin cotton _ _ _ _ _ _.
13. Some terms related to fabrics are jumbled up and given below. Write them in their correct form.
(a) onttoc (b) sinnping (c) vingwea (d) bisref
 
14. State whether the following statements are true or false. If false, correct them.
(a) Silk is a plant fibre.
(b) Jute is obtained from the leaves of a plant.
(c) Weaving is a process of arranging two sets of yarn together.
(d) Cotton yarn on burning gives an odour similar to that of a burning paper.
 
15. The following is an answer given by Boojho to a question asked by his teacher— “Cotton, wool, silk and jute are classified as natural fibres whereas nylon and polyester are classified as synthetic fibres.”
Can you tell what question the teacher has asked?
 
16. Once, Paheli visited a tailor shop and brought home some cuttings of fabric to study their properties. She took two pieces and found that one of the pieces were shrinking when it was burnt with a candle. However the other did not shrink on burning. Can you help her to find out which of the two was a cotton fabric and which a silk fabric?
 
17. One way of making fabric from yarn is weaving, what is the other?
 
SHORT ANSWER QUESTIONS
18. Boojho with perfect eyesight was finding it difficult to pass a thread through the eye of a needle. What can be the possible reason for this?
 
19. In ancient times stitching was not known. People used to simply drape the fabrics around different parts of their body. Even today a number of unstitched fabrics are used by both men and women. Can you give four such examples of clothes?
 
20. Match the articles given in Column I with the articles of Column II
 
21. Fill in the blanks to complete the life story of cotton fibre.
My parents, cotton plants were grown in _______soil and _____-climate. The plants bore fruits called ______ . I, the cotton fibre was separated from seeds in the cotton bolls by the process of
______. Other cotton fibres and myself were made into yarn by the process of ______. The yarn was _______to give beautiful colours and then_______to get cotton fabric.
 
22. Match the terms given in Column I with the statements given in Column II.
Column I Column II
(a) Weaving (i) A single yarn used to make a fabric
(b) Knitting (ii) Combing of cotton fibres to remove seeds
(c) Spinning (iii) Yarns are made from these thin strands
(d) Ginning (iv) These are spun from fibres and then used to make fabrics
(e) Fibre (v) Process of arranging two sets of yarns together to make a fabric
(f) Yarn (vi) Process of making yarn from fibres
23. Fill in the names of useful items made from jute fibres in Fig. 3.1. One such example is given.
Fig. 3.1
 
LONG ANSWER QUESTIONS
24. A cotton shirt, before it reaches you, completes a long journey. Elaborate this journey starting from cotton bolls.
 
25. Describe the two main processes of making fabric from yarn.
1. a 2. b 3. d 4. c 5. c 6. c 7. b
 
8. c 9. c 10. b 11. c
 
12. Yarn, fibre
 
13. (a) Cotton (b) spinning (c) weaving (d) fibre
 
14. (a) F (b) F (c) T (d) T
 
Correct statement
(a) Silk is animals fibres   (b) Jute is obtained from the natural & Synthetic