Fibre to Fabric

Q40. Complete the following table.

Ans.

Q41. Explain the process of obtaining silk from cocoon.

Ans. A pile of cocoons is used for obtaining silk fibres. The cocoons are kept under the sun or boiled or exposed to steam. The silk fibres separate out. The process of taking out threads from the cocoon for use as silk is called reeling the silk. Reeling is done in special machines, which unwind the threads or fibres of silk from the cocoon. Silk fibres are then spun into silk threads, which are woven into silk cloth by weavers.

Q42. What do you know about discovery of silk?

Ans. The exact time of discovery of silk is perhaps unknown. According to an old Chinese legend, the empress Si-lung-Chi was asked by the emperor Huang-ti to find the cause of the damaged leaves of mulberry trees growing in their garden. The empress found white worms eating up mulberry leaves. She also noticed that they were spinning shiny cocoons around them. Accidentally a cocoon dropped into her cup of tea and a tangle of delicate threads separated from the cocoon. Silk industry began in China and was kept a closely guarded secret for hundreds of years.

Q43. Explain various steps involved in the process of making wool?

Ans. Steps

Shearing - The fleece of the sheep along with a thin layer of skin is removed from its body using shearing machine.

Scouring - The sheared skin with hair is thoroughly washed in tanks to remove grease, dust and dirt. It is done by machines.

Sorting- The hairy skin is sent to a factory where hair of different textures are separated or sorted.

Picking of Burrs - The small fluffy fibres, called burrs, are picked out from the hair.

Dyeing - The fibres can be dyed in various colours.

Combing and Rolling - The fibres are straightened, combed and rolled into yarn.

Q44. Write a note on rearing silkworm.

Ans. Rearing silkworms:

                            i.        A female silk moth lays hundreds of eggs at a time. The eggs are stored carefully on strips of cloth or paper and sold to silkworm farmers.

                           ii.        The farmers keep eggs under hygienic conditions and under suitable conditions of temperature and humidity.

                          iii.        The eggs are warmed to a suitable temperature for the larvae to hatch from eggs. The larvae are kept in clean bamboo trays along with freshly chopped mulberry leaves.

                          iv.        After 25 to 30 days, the caterpillars stop eating and move to a tiny chamber of bamboo in the tray to spin cocoons.

                           v.        Small racks or twigs may be provided in the trays to which cocoons get attached. The caterpillar or silkworm spins the cocoon inside which develops the silk moth.