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www.GOALias.blogspot.comprotein which hardens on exposure toair and becomes silk fibre. Soon thecaterpillar completely covers itself by silkfibres. This covering is known ascocoon. The further development of themoth continues inside the cocoon(Fig. 3.9). Silk fibres are used forweaving silk cloth. Can you imagine thatthe soft silk yarn is as strong as acomparable thread of steel!The silk yarn (thread) is obtainedfrom the cocoon of the silk moth. Thereis a variety of silk moths which look verydifferent from one another and the silkyarn they yield is different in texture(coarse, smooth, shiny, etc.). Thus,tassar silk, mooga silk, kosa silk, etc.,are obtained from cocoons spun bydifferent types of moths. The mostcommon silk moth is the mulberry silkmoth. The silk fibre from the cocoon ofthis moth is soft, lustrous and elasticand can be dyed in beautiful colours.Sericulture or culture of silkwormsis a very old occupation in India. Indiaproduces plenty of silk on a commercialscale.Activity 3.5Collect pieces of silk cloth of varioustypes and paste them in your scrapbook. You can find them in a tailor’sshop among the heap of waste cut pieces.Take help of your mother, aunt orteacher and identify the types of silksuch as mulberry silk, tassar silk, erisilk, mooga silk, etc. Compare thetexture of these silks with that of theartificial silk pieces, which containsynthetic fibres. Try and collect picturesof different moths whose caterpillarsprovide the various types of silk.Activity 3.6Take an artificial (synthetic) silk threadand a pure silk thread. Burn thesethreads carefully. Did you notice anydifference in the smell while burning?Now, burn a woollen fibre carefully.Did it smell like burning of artificialsilk or that of pure silk? Can youexplain why?To remember when the cocoon stageis reached in the life history of the silkmoth, try the following activity.Activity 3.7Photocopy Fig. 3.9. Cut out pictures ofthe stages of the life history of the silkmoth, and paste them on pieces ofcardboard or chart paper. Jumblethem. Now try and arrange the stagesin the correct sequence. Whoever doesit fastest wins.You may also describe the life historyin your own words. Write it down in yourscrap book.In India, women are significantly involved in various kinds of industries relatedto silk production. These are rearing of silkworms, reeling of silk from cocoonsand processing of raw silk into fabrics. By their enterprise, they contribute tothe nation’s economy. China leads the world in silk production. India also ranksamong the leading silk producing countries.FIBRETO FABRIC2929