Science · Class 7
Fibre to Fabric
Animal fibres (wool, silk) and processing from cocoon to fabric.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Class 7 extends fibre study to animal fibres — wool and silk. Covers sheep rearing, silk moth life cycle, processing wool and silk, and occupational hazards in sericulture and shearing.
Wool Production
- Sheep breeds: Lohi, Rampur bushair, Nali (India)
- Rearing, shearing, scouring, sorting, grading, dyeing, spinning
- Wool from sheep, yak, camel, goat (pashmina, angora)
Silk Production
- Silkworm (Bombyx mori) → cocoon of silk fibre
- Stages: egg → larva → pupa → adult moth
- Sericulture: rearing silkworms for silk
- Reeling: unwinding silk from cocoons
Health Hazards
- Shearers may get cuts; sorter's disease (anthrax)
- Boiling cocoons kills pupa — ethical concerns in ahimsa silk
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Silk life cycle
Arrange: egg, larva, pupa, adult moth.
- 1Egg hatches to larva (feeds mulberry)
- 2Larva spins cocoon → pupa
- 3Adult moth emerges
Answer
Egg → Larva → Pupa → Adult
Wool source
Name two animals that yield wool.
- 1Sheep most common
- 2Yak, camel, goat also provide wool
Answer
Sheep, yak, camel, or goat
Key Points to Remember
- ✓ Pashmina from Kashmiri goat
- ✓ Mulberry leaves feed silkworms
- ✓ Cotton is plant fibre; wool and silk are animal
Exam Tips
- • Draw silk moth life cycle
- • List steps from fleece to wool yarn
- • Distinguish natural and synthetic fibres
Practice MCQs — Fibre to Fabric
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Silk fibre comes from: