Question

How is silk fibre is obtained from the cocoon?

Answer 1

Hint: Rearing of silkworm is known as sericulture. Silk is obtained from the cocoon stage of the silkworm. Cocoon is made by the pupa when it is undergoing metamorphosis to become an adult. The cocoon is made up of one fine thread of silk.

Complete answer:
We knew that the silk is obtained from the silkworm. The silk is obtained from the cocoon stage of the lifecycle of the silkworm. The silkworm starts its life cycle as the eggs and matures into the caterpillar which feeds continuously on the mulberry leaves. When the feeding is over, they construct a cocoon around them and turns into a pupa. After some days, the butterfly or the adult moth breaks open the cocoon and comes out.

The cocoon is made up of a single strand of fine silk thread. In order to get the silk, the cocoon has to be collected and the threads have to be pulled out. This is done by putting the cocoons in the hot water or dry baking the cocoons so that the pupa dies and does not come by breaking the cocoon. Boiling the cocoon also reduces the brittleness of the silk. This helps in pulling out the threads of the silk fibres. It is known as the reeling of silk.

After reeling, the fibres are drawn in yarns and made into fabrics.

Note: The silk is a soft shiny fibre that is used in making silk fabric. It has a lot of economic importance. Silk rearing was first started in China. It is a popular luxury fabric in China.