NCERT Solutions for Class 7th Science
Chapter 3. Fibre to Fabric
- The animal fibre are Wool and silk.
- Wool obtains from animals like sheep, goat, yak and some other animals.
- The process of selecting parents for obtaining special characters in their offspring,such a soft under hair in the sheep,is termed selective’.
- The sheep has two types of fibres. (i) The coarse beard hair (ii) The fine soft.
- The rearing of silkworms for obtaining silk is called sericulture.
- The caterpillar completely covers itself by silk fibers and turns into pupa. This covering is known as cocoon.
- The female silk moth lays eggs, from which hatch larvae which are called caterpillars or silkworms.
- When the caterpillar is ready to enter the next stage of its life history called pupa.
- The caterpillar completely covers itself by silk fibres. This covering is known as cocoon.
- The silk yarn (thread) is obtained from the cocoon of the silk moth.
- The most common silk moth is the mulberry silk moth.
- The process of taking out threads from the cocoon for use as silk
is called reeling the silk.
- Silk fibres are made of a protein.