Fibre to Fabric class 7 | worksheet and printable
Fibre to Fabric class 7. Download Fibre to Fabric class 7 worksheet based on the latest ncert syllabus including MCQ on fibre to fabric, define, long questions, fill in the blanks and more.
Points to remember
fibres are obtained from animals. Wool is obtained from the fleece (hair) of sheep or yak. Silk fibres come from cocoons of the silk moth.
Wool comes from sheep, goat, yak and some other animals. These wool-yielding animals bear hair on their body
Did you know Some breeds of sheep possess only fine under-hair. Their parents are specially chosen to give birth to sheep which have only soft underhair. This process of selecting parents for obtaining special characters in their offspring, such as soft under hair in sheep, is termed ‘selective breeding’.
Wool commonly available in the market is sheep wool. wool is common in Tibet and Ladakh. Mohair is obtained from angora goats found in hilly regions such as Jammu
and Kashmir The fur (hair) on the body of camels is also used as wool
The wool industry is an important means of livelihood for many people in our country. But sorter’s job is risky as sometimes they get infected by a bacterium, anthrax, which
causes a fatal blood disease called sorter’s disease.
Silk fibres are also animal fibres. Silkworms spin the ‘silk fibres’. The rearing of silkworms for obtaining silk is called sericulture
The female silk moth lays eggs, from which hatch larvae which are called caterpillars or silkworms. They grow in size and when the caterpillar is ready to enter the next stage of its life history called pupa, it first weaves a net to hold itself. Then it swings its head from side to side in the form of the figure of eight . During these movements of the head, the caterpillar secretes fibre made of a protein that hardens on exposure to air and becomes silk fibre. Soon the caterpillar completely covers itself by silk fibres and turns into pupa. This covering is known as a cocoon.
tassar silk, mooga silk, kosa silk, etc are obtained from cocoons spun by different types of moths. The most common silk moth is the mulberry silk moth. The silk fibre from the cocoon of this moth is soft, lustrous and elastic and can be dyed in beautiful colours.
Discovery of silk
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. Later on, traders and travellers introduced silk to other countries. The route they travelled is still called the ‘silk route.