Fibre to Fabric is Chapter 3 taken from JKBOSE and NCERT textbook of Science for students of Class 7th. In the previous post, I provided you with Questions and Answers for Chapter 2 Nutrition in Animals. This post is about Fibre to Fabric Class 7th Question Answers. Before we move on to solutions you must have your basics clear. So, let me begin by giving you a brief overview of what you have studied in this chapter.
Fibre to Fabric Class 7th Question Answers
Overview of Chapter
- ANIMAL FIBRES- WOOL AND SILK.
- WOOL AND ANIMALS THAT YIELD WOOL.
- FROM FIBRES TO WOOL- REARING AND BREEDING OF SHEEP.
- PROCESSING OF FIBRES TO WOOL.
- SILK AND LIFE HISTORY OF SILK MOTH.
- FROM COCOON TO SILK.
- REARING OF SILKWORMS.
- PROCESSING OF SILK.
ANIMAL FIBRES- WOOL AND SILK: In class 6th you have learnt about plant fibres like cotton, jute and flax. This chapter is about the fibres obtained from animals and hence these are termed animal fibres. The two most important animal fibres are wool and silk.
WOOL AND ANIMALS THAT YIELD WOOL: Wool is one of the most common animal fibres. It comes from soft and curly hair which comes from the body of sheep. The wool comes from the fleece of the sheep. Wool mainly comes from sheep. Besides this, there are other animals like goats, yak, camel, llamas and alpacas.
FROM FIBRES TO WOOL – REARING AND BREEDING OF SHEEP: Wool mainly comes from the hair of sheep. For this purpose, sheep are reared and bred. The hair from the body of sheep is cut and processed into wool. Rearing sheep means looking after the sheep by providing them with food, shelter and health care. The person who looks after the sheep are named shepherds. The sheep are bred to obtain breeds of sheep which yield a good quantity of wool.
PROCESSING OF FIBRES TO WOOL: The wool that we use for knitting and weaving fabrics is the finished product of a long process which involves the following steps:
- Shearing.
- Scouring.
- Sorting.
- Removing of burrs.
- Dying of Fibres.
- Straightening, combing and rolling of yarns.
SILK AND LIFE HISTORY OF SILK MOTH: Silk is a natural fibre obtained from the silk moth. Silkworms spin the ‘silk fibres’. The silk fibre is made up of protein. It is the strongest natural fibre. The rearing of silkworms for obtaining silk is called sericulture.
Life History of Silk moth: The female silk moth lays eggs on the leaves of a mulberry tree. The eggs of silk moth hatch to form worm-like larvae. The larvae of silk moths are called ‘caterpillars’ or ‘silkworms’. They feed on the leaves of the mulberry tree and grow bigger. The silk is formed in liquid form in the two glands present in the silkworm’s head. It is secreted in liquid form through the tiny opening in the head of a silkworm and solidifies on exposure to air and it becomes silk fibre.
After some time, the silkworm covers itself completely with silk fibres. This silky covering spun by silkworm around its body is called a cocoon. It is made by the silkworm to protect its development as a ‘pupa’. The silkworm continues to develop inside the cocoon to form a silk moth. When the pupa develops fully to become an adult silk moth, the cocoon splits up and the silk moth comes out. The adult female silk moth then lays more eggs. And, in this manner, the life cycle of the silk moth is completed.
FROM COCOON TO SILK: For obtaining silk, silk moths are reared and their cocoons are collected to get silk threads.
REARING OF SILKWORMS: A female silk moth lays hundreds of eggs at a time. The eggs are stored carefully on strips of cloth or paper and sold to silkworm farmers. The farmers keep eggs under hygienic conditions and suitable conditions of temperature and humidity.
The eggs are warmed to a suitable temperature for the larvae to hatch from the eggs. This is done when Mulberry trees bear a fresh crop of leaves. The larvae, called caterpillars or silkworms, eat day and night and increase enormously in size.
The larvae are kept in clean bamboo trays along with freshly chopped mulberry leaves. After 25 to 30 days, the caterpillars stop eating and move to a tiny chamber of bamboo in the tray to spin cocoons. Small racks of twigs may be provided in the trays to which cocoons get attached. The caterpillar or silkworm spins the cocoon inside which develops the silk moth.
PROCESSING OF SILK: The processing of silk fibres involves separating silk fibres from the cocoon. It can be done by any of these methods like exposing the cocoon to sunlight, boiling them or exposing them to steam. The process of taking out threads from the cocoon and use as silk is called reeling of silk. It is done by special machines. The silk fires are then spun to form silk threads, which are woven into silk cloth by weavers.
Fibre to Fabric Class 7 Questions
- 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?
Ans. The hairy skin of the black sheep has wool in it.
(b) What is meant by the white fleece of the lamb?
Ans. The white fleece of the lamb means the white-coloured hairy skin of the lamb.
- The silkworm is (a) a caterpillar, and (b) a larva. Choose the correct option.
(i) a (ii) b (iii) both a and b (iv) neither a nor b.
Ans. (iii) both a and b
- Which of the following does not yield wool?
(i) Yak (ii) Camel (iii) Goat (iv) Woolly dog
Ans. iv) Woolly Dog
- What is meant by the following terms?
(i) Rearing (ii) Shearing (iii) Sericulture
Ans. i) Rearing: The bringing up and looking after of animals by providing them food, shelter and health care for deriving benefits from them is called rearing. For example. Rearing of sheep for wool and meat, rearing of silkworms for obtaining silk etc.
ii) Shearing: The process of removing fleece/hairy skin from the body of wool-yielding animals using pair of scissors or shaving machines is termed shearing.
iii) Sericulture: The art of rearing silkworms on large scale for the production of silk is termed sericulture.
5. The science of raising of silkworms so as to obtain silk cocoons is called:
a) Apiculture b) Horticulture c) Sericulture d) Pisciculture
Ans. Sericulture.
6. The hair on the skin of the sheep, yak, etc, from which wool can be obtained.
a) Wool b) Fleece c) Silk d) Yarn
Ans. Fleece
7. The proper sequence of the life cycle of a silkworm is:
a) Egg → Pupa →Caterpillar
b) Pupa→ Egg → Caterpillar
c) Eggs → Caterpillar → Pupa
d) Caterpillar → Egg → Pupa
Ans. Eggs → Caterpillar → Pupa
8. Which of the following diseases is caused due to wool industry?
a) Typhoid
b) Cholera
c) Tetanus
d) Anthrax
Ans. Anthrax
9. Given below is a sequence of steps in the processing of wool. Which are the missing steps? Add them.
Shearing, __________, sorting, __________, __________.
Ans. 1. Shearing 2. Scouring 3. Sorting 4. Picking of Burrs 5. Dyeing 6. Rolling into Yarns
10. Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
- Out of the following, which are the two terms related to silk production?
Sericulture, floriculture, moriculture, apiculture and silviculture.
Hints: (i) Silk production involves the cultivation of mulberry leaves and rearing silkworms.
(ii) Scientific name of mulberry is Morus alba.
Ans. The terms sericulture and moriculture are related to silk production.
- 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 silkworm |
| 4. Cocoon | (d) Reeling |
| (e) Cleaning sheared skin |
Ans.
| Column I | Column II |
|---|---|
| 1. Scouring | e) Cleaning sheared skin |
| 2. Mulberry leaves | c) Food of silkworm |
| 3. Yak | b) Wool-yielding animal |
| 4. Cocoon | a) Yields silk fibres |
- 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
(A) 1: Keeps warm
2: Its leaves are eaten by silkworms
3: Hatches from the egg of a moth
Ans.
That’s all about Fibre to Fabric Class 7th Question Answers. Hope it has helped. Do share your views about this post in the comment section below.
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