Science 1 Marks Question

The main aim to rear the sheep is to obtain wool.

Workers in wool industry get infected by a bacterium, anthrax, which causes a fatal blood disease called sorter's disease.

During shearing the uppermost layer of sheep’s skin which is dead is removed. Therefore, it does not hurt the sheep.

We wear clothes according to the climate. In summers we wear clothes that keep us cool and in winters we wear clothes which keep us warm.

Usually shearing of wool is done only in summer as sheep do not to survive without their protective coat of hair in winter.

The process of removing the fleece of the sheep along with a thin layer of skin is from its body is called shearing. It is done by using shearing machine.

Wool is obtained from the fleece or hair of sheep.

A thick coat of hair helps in trapping a lot of air. As, air is a poor conductor of heat, it keep these animals warm.

Silkworm.

Caterpillars should not be collected with bare hands because skin of caterpillars may cause allergy.

Silk fibres come from cocoon of silk worm.

False.
Wool can be made from sheep, yak, llama, camel, alpaca and goats.

Wool is the soft, curly fibres obtained from the fleece of sheep, goat and yak etc., it clothes made from wool keeps us warm.

People working in the wool industry sometimes get infected by a bacterium called anthrax, during the sorting (separating) the fleece of sheep into fibres of different qualities. It leads to a fatal blood disease called sorter’s disease.

Silk and Wool fibres are obtained from animals.

White fleece means the hairy skin which is white in colour.

Sheep, goat yak etc.

The hairy skin called fleece have wool in black sheep.

Wool, silk.

Cotton clothes are thin and do not have spaces in their fabrics through which air can be trapped, to keep us warm thus Cotton clothes do not prevents heat coming out of our body.

Poor.

Keratin is the chief component of wool fibres.

True.

Selective breeding is defined as the breeding of plants and animals to obtain desirable characteristics.

The sheep's hair are Sheared off from its body, scoured, sorted, dried, dyed, spun and woven to yield wool.

Hair trap a lot of air, which is a poor conductor of heat.

The larva (or caterpillar) of a silk moth makes the silk fibre.

The sheared hair is cleaned and washed in tanks to remove grease, dust and dirt. This is called scouring.

Protein.