NCERT Solutions Science Chapter 3 Fibre to Fabric for Class 7th
Chapter 3 “Fibre to Fabric” from the NCERT Class 7 Science textbook:
Summary of “Fibre to Fabric”
Introduction to Fibres:
- Fibres are the basic building blocks of fabrics. They can be classified into natural fibres (derived from plants and animals) and synthetic fibres (man-made).
Natural Fibres:
Plant Fibres:
- Obtained from parts of plants such as seeds, stems, or leaves.
- Examples: Cotton (from cotton plants), jute (from jute plants), and flax (from flax plants).
Animal Fibres:
- Sourced from animals.
- Examples: Wool (from sheep), silk (from silkworms), and others like cashmere (from goats).
Production of Fibres:
- Cotton: The cotton boll is harvested, and the fibres are separated from seeds through a process called ginning.
- Wool: Obtained by shearing sheep, washing the fleece, and then processing it into wool.
- Silk: Produced from silkworm cocoons through sericulture. The cocoons are boiled to extract silk threads.
Processing Fibres into Fabrics:
- Spinning: The process of twisting fibres together to make yarn.
- Weaving: Interlacing two sets of yarn (warp and weft) to create fabric.
- Knitting: A method that uses a single yarn to create a fabric by making loops.
Synthetic Fibres:
- Made from chemicals, often derived from petroleum.
- Examples include polyester, nylon, and acrylic.
- They have properties like durability and resistance to wrinkles but may not be as breathable as natural fibres
NCERT Solutions Science Chapter 3 Fibre to Fabric 2024-2025
1. 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?
(b) What is meant by the white fleece of the lamb?
Solution:
a) Wool is obtained from hairy fibres of the sheep.
b) White fleece of the lamb refers to the white colour of their fur.
2. The silkworm is (a) a caterpillar, (b) a larva.
Choose the correct option. (i) a (ii) b (iii) both a and b (iv) neither a nor b.
Solution:
(iii) both a and b
3. Which of the following does not yield wool?
(i) Yak (ii) Camel (iii) Goat (iv) Woolly dog
Solution:
The answer is (iv) Woolly dog
4.What is meant by the following terms? (i) Rearing (ii) Shearing (iii) Sericulture
Solution:
i) Raising of domestic animals like sheep, goat, yak, cow and buffaloes for commercial purposes such as for milk and fur is known as rearing.
ii) Shearing is a process of removal of animal hair by using machines similar to those used by barbers.
ii) Rearing of silkworms to get silk is known as Sericulture.
5. Given below is a sequence of steps in the processing of wool. Which are the missing steps? Add them.
Shearing, __________, sorting, __________, __________, _________.
Solution:
Shearing, Scouring, sorting, picking of burrs, dying of fibres, making of yarn.
6. Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
Solution:
7. Out of the following, which are the two terms related to silk production?
Sericulture, floriculture, moriculture, apiculture and silviculture.
Hints: (i) Silk production involves cultivation of mulberry leaves and rearing silkworms. (ii) Scientific name of mulberry is Morus alba
Solution:
Sericulture and moriculture
8. Match the words of Column I with those given in Column II:
| Column-I | Column-I |
| 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 |
Solution:
| Column-I | Column-I |
| 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 |