Fibre to Fabric

Wool and silk are animal fibres. Wool comes from the fleece, or hair, of sheep, goats, yaks, camels, llamas and alpacas; the Angora goat of Jammu and Kashmir gives soft wool and the Kashmiri goat gives the fine pashmina used in shawls. Hairy skin traps air, a poor conductor of heat, keeping sheep warm. By selective breeding, farmers rear breeds with soft under-hair, such as Lohi, Rampur bushair, Nali and Bakharwal. Fleece is turned into wool through shearing, scouring, sorting, removing burrs, dyeing, and finally straightening, combing and rolling the fibres into yarn. Sorters may catch anthrax, a serious bacterial disease, an occupational hazard. Silk fibres come from the cocoons of the silk moth, and rearing silkworms for silk is called sericulture. The life cycle of the silk moth has four stages: egg, larva (caterpillar or silkworm), pupa and adult moth. The caterpillar feeds on mulberry leaves and spins a protective cocoon of silk around itself. The cocoons are boiled or steamed and the threads are unwound in a process called reeling. Silk was first discovered in China.

Detailed Worksheet: Fibre to Fabric Section A - Definitions (10 marks) 1. What are animal fibres? Name two and the animals that give them. (2 marks) 2. What is fleece? Why does it keep sheep warm? (2 marks) 3. What is selective breeding? Why is it done in sheep? (2 marks) 4. Define sericulture and reeling. (2 marks) 5. What is a cocoon? Who makes it and why? (2 marks) Section B - Calculations and Applications (15 marks) 6. Arrange the steps of processing fibres into wool in the correct order: dyeing, shearing, sorting, scouring, rolling into yarn, picking out burrs. (3 marks) 7. Match each sheep breed with its state and type of wool: Lohi, Rampur bushair, Nali, Bakharwal (states: Rajasthan and Punjab, Uttar Pradesh and Himachal Pradesh, Rajasthan, Haryana and Punjab, Jammu and Kashmir). (3 marks) 8. Name the animal that gives each: (i) pashmina (ii) mohair or Angora wool (iii) wool in Tibet and Ladakh (iv) wool in South America, two animals. (3 marks) 9. Why is shearing done in summer? Why does it not hurt the sheep? (3 marks) 10. Name four varieties of silk produced in India and the most common type. Why is silk called a protein fibre? (3 marks) Section C - Diagrams (10 marks) 11. Draw a labelled diagram of the life cycle of the silk moth showing the egg, larva, pupa (cocoon) and adult moth. (4 marks) 12. Draw a flowchart showing the steps from rearing sheep to obtaining woollen yarn. (3 marks) 13. Draw a flowchart showing the steps from silkworm eggs to silk thread. (3 marks) Section D - Analysis and Higher-order Thinking (15 marks) 14. A worker in a wool-sorting unit fell sick with fever and breathlessness. (i) Which disease might he have? (ii) What causes it? (iii) What is an occupational hazard? (iv) Suggest two safety measures for sorters. (v) Who should be responsible for their safety? (5 marks) 15. The Silk Route linked China with Europe and Asia. (i) Where was silk first discovered? (ii) What was the Silk Route? (iii) Why did silk become so valuable? (iv) What do you think is the importance of this route in history? (5 marks) 16. Some people avoid silk because the pupae are killed in the reeling process. (i) Why are cocoons boiled? (ii) What would happen if the moth were allowed to emerge? (iii) Give your opinion on this issue. (iv) Name one alternative fibre. (5 marks) Instructions: Time allowed 2 hours. Attempt all sections. Write processes in the correct order and label diagrams clearly.