Question

Which of the following is not a plant fibre?
A) Flax
B) Coir
C) Silk
D) Hemp

Answer 1

Hint: Fiber is a hair like strand of material. Plant fibre is one of the types of natural fibre that consist of cellulose, hemi cellulose, ligin, pectin. Natural fibers are made by plants, animals and geological processes. Animal fiber and mineral fiber are another classification of natural fiber.

Complete answer:
Plant fibers are cotton, jute, coir, hemp, flax.
 Properties of plant fiber:
>The fiber is normally a rigid, crystalline cellulose microfibril- reinforced amorphous lignin and with hemicellulosic matrix.
>Mechanical structure of plant fibers is much lower when compared to reinforcing glass fiber.
>Somehow because of the low density, their properties for the strength and the stiffness of the plant fibers are comparable to the values of glass fibers.

Flax is a member of genus linum in the family linaceae. Hemp is the name of soft, durable fiber that is cultivated from plants of the cannabis genus, cultivated for commercial use. Coir is found between the hard, internal shell and outer coat of coconut.

Silk is a natural protein fibres, some forms of which can be woven into textile. The best silk is obtained from cocoons of larvae of mulberry silkworm (bombyx mori) reared in captivity. Therefore, silk is not obtained from plant fibers.

Thus, the correct answer is option (C).

Note: Jute is a long, soft, shiny vegetable fiber that can be spun into coarse, strong threads. Jute is one of the most inexpensive natural fibers. Classification of animal fiber are animal hair (wool, human hair, feather), silk fiber. Mineral fiber is asbestos.