Class 7 Science Chapter 3 Fibre to Fabric Notes and Questions Answers | NCERT Solutions for Exam Preparation
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Class 7 Science Chapter 3 – Fibre to Fabric Notes and Questions Answers

Welcome to our detailed and easy-to-understand notes and question answers on Fibre to Fabric (Class 7 Science). This post is designed to help you prepare effectively for school exams as well as competitive tests. The chapter explains the process of obtaining fibres from animals, the steps involved in processing them, and their uses. Here, you will find well-structured notes followed by important questions divided into multiple categories for your revision.

📘 Class 7 Science Fibre to Fabric – Easy Notes

Introduction to Fibres

Fibres are thin, thread-like structures that can be spun into yarn and woven into fabrics. Fabrics are an essential part of human life, providing us with clothes and other materials of daily use. In this chapter, we mainly study animal fibres such as wool and silk.

Wool – Fibre from Animals

Wool is obtained from the fleece (hair) of sheep, goats, camels, and yaks. It is a natural fibre made up of proteins. The quality of wool depends on the breed of sheep and the region they are reared in. India is famous for breeds like Kashmiri goats (pashmina), Angora rabbits, and Ladakhi yaks.

Steps of Processing Wool

  1. Shearing: Removal of fleece along with a thin layer of skin.
  2. Scouring: Washing of sheared hair to remove dirt, grease, and sweat.
  3. Sorting: Separation of fibres according to texture and quality.
  4. Combing: Removing burrs and making fibres smoother.
  5. Dyeing: Colouring the fibres as per requirement.
  6. Spinning: Converting fibres into yarn.
  7. Weaving/Knitting: Producing fabrics from yarn.

Silk – A Natural Protein Fibre

Silk is obtained from the cocoons of silkworms. It is one of the strongest natural fibres and has a natural shine. The main species of silkworm used in India is Bombyx mori. India is among the top producers of silk in the world, producing varieties like mulberry silk, tasar silk, eri silk, and muga silk.

Life Cycle of Silkworm

  1. Egg: Female silk moth lays eggs on mulberry leaves.
  2. Larva (Caterpillar): The eggs hatch into caterpillars which feed on mulberry leaves.
  3. Pupa: The caterpillar spins a cocoon made of silk fibre.
  4. Adult moth: The pupa grows into an adult moth, continuing the cycle.

Processing Silk

  1. Collection of cocoons.
  2. Boiling of cocoons in hot water to soften the silk fibres.
  3. Reeling of silk – unwinding long silk threads from cocoon.
  4. Spinning and weaving into silk fabrics.

Uses of Wool and Silk

  • Wool: Sweaters, shawls, blankets, carpets, coats, and warm clothing.
  • Silk: Sarees, ties, dresses, upholstery, decorative items, and embroidery.

Important Notes

  • Both wool and silk are animal fibres.
  • Wool comes from the hair/fleece of animals like sheep and yak.
  • Silk comes from cocoons spun by silkworms.
  • India is famous for pashmina wool and mulberry silk.
  • Wool is warm, silk is shiny and smooth.

✍️ Class 7 Science Fibre to Fabric – Questions & Answers

MCQs (Multiple Choice Questions)

  1. Wool is obtained from:
    a) Silkworm
    b) Sheep
    c) Cotton plant
    d) Jute plant
    Answer: b) Sheep
  2. Which of the following is not an animal fibre?
    a) Wool
    b) Silk
    c) Jute
    d) Pashmina
    Answer: c) Jute
  3. The process of removing fleece from sheep is called:
    a) Scouring
    b) Shearing
    c) Sorting
    d) Combing
    Answer: b) Shearing
  4. The larva of silk moth feeds on:
    a) Grass
    b) Cotton leaves
    c) Mulberry leaves
    d) Mango leaves
    Answer: c) Mulberry leaves
  5. Pashmina wool is obtained from:
    a) Goat
    b) Rabbit
    c) Yak
    d) Camel
    Answer: a) Goat
  6. The process of making silk fibre from cocoon is called:
    a) Reeling
    b) Weaving
    c) Sorting
    d) Combing
    Answer: a) Reeling
  7. Which silk is unique to Assam?
    a) Muga silk
    b) Tasar silk
    c) Eri silk
    d) Mulberry silk
    Answer: a) Muga silk

Very Short Answer Questions

  1. Name two fibres obtained from animals. Answer: Wool and Silk.
  2. What is shearing? Answer: The process of removing fleece of sheep along with thin skin.
  3. Which insect gives silk? Answer: Silkworm (silk moth larva).
  4. Name the natural protein fibre obtained from silkworm. Answer: Silk.
  5. Which state of India is famous for pashmina wool? Answer: Jammu & Kashmir.
  6. What is the food of silkworms? Answer: Mulberry leaves.
  7. Name the step in wool processing where fibres are washed. Answer: Scouring.

Short Answer Questions

  1. Differentiate between natural and synthetic fibres. Answer: Natural fibres are obtained from plants and animals (e.g., cotton, wool, silk), while synthetic fibres are man-made (e.g., nylon, polyester).
  2. What is sorting in wool processing? Answer: Sorting is the separation of fibres according to their quality and texture after scouring.
  3. Write two characteristics of silk fibre. Answer: (i) It has a natural shine. (ii) It is strong and smooth.
  4. Name the main breeds of sheep found in India. Answer: Lohi, Rampur Bushair, Nali, Bakharwal, Patanwadi, Marwari.
  5. What is reeling of silk? Answer: Reeling is the process of unwinding silk threads from cocoons.
  6. Why are woollen clothes preferred in winter? Answer: Because wool fibres trap air, which is a poor conductor of heat, keeping us warm.
  7. Write two uses of silk. Answer: Used for making sarees, dresses, ties, and decorative materials.

Long Answer Questions

  1. Describe the process of wool production. Answer: Wool production involves the following steps: (i) Shearing – fleece removal, (ii) Scouring – washing to remove dirt, (iii) Sorting – separation by quality, (iv) Combing – removal of burrs, (v) Dyeing – adding colours, (vi) Spinning – fibres into yarn, (vii) Weaving/Knitting – yarn into fabric.
  2. Explain the life cycle of a silkworm. Answer: The female silk moth lays eggs on mulberry leaves. These hatch into larvae (caterpillars) that feed on leaves. They spin cocoons made of silk fibre. Inside the cocoon, the pupa develops into an adult moth, completing the cycle.
  3. Write a short note on Pashmina wool. Answer: Pashmina wool is obtained from the soft under-fur of Kashmiri goats. It is extremely fine, soft, and warm, and is used to make shawls and sweaters. It is one of the costliest varieties of wool.
  4. What are the steps involved in silk processing? Answer: Silk processing involves: (i) Collecting cocoons, (ii) Boiling them in hot water, (iii) Reeling the silk fibres, (iv) Spinning and weaving into fabric.
  5. Differentiate between wool and silk. Answer: Wool is obtained from animal hair, is warm, and used in winters. Silk is obtained from silkworms, shiny, smooth, and used for making luxury fabrics.
  6. How does rearing of silkworms take place? Answer: Silkworm rearing involves keeping silkworms in clean trays, feeding them mulberry leaves, maintaining hygiene, and then collecting their cocoons for silk fibre extraction.
  7. Why are animal fibres considered important for human life? Answer: Animal fibres like wool and silk are natural, comfortable, durable, and useful for making warm and decorative clothes. They play a crucial role in human culture and economy.

These notes and solutions are prepared to help Class 7 students revise Chapter 3 – Fibre to Fabric in a clear and easy manner. Practice these questions to strengthen your preparation.