CBSE Questions for Class 7 Chemistry Fibre To Fabric Quiz 1 - MCQExams.com

Natural fibers are hairlike raw material directly obtainable from an animal, vegetable, or mineral source and convertible into nonwoven fabrics such as felt or paper or, after spinning into yarns, into woven cloth. A natural fiber may be further defined as an agglomeration of cells in which the diameter is negligible in comparison with the length examples: cellulose types such as cotton, wool, grains, and straw.
Synthetic fibers are fibers that are human-made by chemical synthesis, as opposed to natural fibers. In general, synthetic fibers are created by extruding fiber-forming materials through spinnerets into air and water, forming a thread. These fibers are called synthetic or artificial fibers. Some fibers (such as the diverse family of rayons) are manufactured from plant-derived cellulose and are thus semi-synthetic, whereas others are totally synthetic, being made from crudes and intermediates including petroleum, coal, limestone, air, and water.

Sericulture, also known as silk farming, is the process of rearing silkworms in order to produce silk.

Pashmina a very fine quality of wool is obtained from goats.

Synthetic fibres are prepared by using chemicals. These are made of small units that join together to form long chains. 

Sheep, goat, Camel, Yak, etc. bear hair of two different types coarse hair and fine soft hair. Fine soft hair is found close to the skin in these animals. The fine soft under hair is called fleece. Fibre for wool is obtained from the fleece (hair) of such animals and hence such animals are called wool-bearing animals.

Sericulture is a process of rearing of silkworm to obtain silk.

The workers in the sericulture industries face many health problems like asthma, bronchitis, etc. These disorders happen because the workers are exposed to vapours arising from boiling, cooking and reeling the cocoons, causing breathing problems.

There are many animals that bear a thick coat of hair on their body which gives wool to us.

Animals fibres are those which largely consist of protein. Some of the animals have the property to provide such kind of feather or fur which can be used to produce wool. All the given examples are animal fiber use to form a different type of wool.

Silk is a natural protein fibre which can be woven into textiles. 

Because insects have the ability to digest silk and wool. Examples of insects that damage the clothes are-silverfish, cockroach, moth etc. 

Explanation:

Pisciculture: Also known as fish farming, it is the rearing, breading, and transplantation of fishes. 

Sericulture: It is the rearing of silkworms in order to obtain silk from their pupa.

Polyculture: It is the planting of two different crops in the same field at different times. It helps to replenish lost minerals.

Arboriculture: It is the cultivation and management of trees, shrubs, perennial woods, etc.

Hence, correct option is B.

Wool is not obtained from the skin and toes of the sheep. The fleece (hair) of the sheep consists of soft woollen fibers, which are used to obtain wool. So the correct answer is option C