Question
Question: Which is a useful product of epidermal origin? (A) Saffron (B) Cotton fibre (C) Clove (D) Ju...
Which is a useful product of epidermal origin?
(A) Saffron
(B) Cotton fibre
(C) Clove
(D) Jute
Solution
Plant epidermis is nothing but the covering of different parts of plants like stem, leaf, seed, etc. It is a single cell layer that functions as a border between the plant parts and outer surroundings. The epidermis is usually classified as dermal tissue which also secretes a waxy layer known as Cuticle in order to prevent water loss.
Complete answer:
Fibres are the longest cells in the plant body. They have thick cell walls that contain simple and bordered pits. On the basis of position, fibres are divided into surface fibres, wood fibres and Bast fibres. Cotton fibres are an example of seed surface fibres. They are the epidermal fibres i.e. they belong to epidermal origin of the seed. Cotton fibres are the outgrowth of seed coats. They are composed of cellulose and are non-lignified. Hence, cotton fibres are not true fibres. There are two types of fibres that are found in cotton fibres. Long fibres also known as Lint and small fibres called Fuzz. Lint fibres are useful products of the cloth industry whereas fuzz are filling fibres. The second most produced fibres are Jute fibres. These are the longest commercial fibres which are an example of Bast fibres also known as extra xylary fibres. Saffron and cloves are the popular spices. Saffron is an example of Corm which is an underground modification of stem.
Therefore the correct option is (B) Cotton Fibre.
Note: Cotton belongs to the Malvaceae family and the Gossypium genus. Most of the economically important fibre plants belong to the Malvaceae family. Cotton fibres are obtained from the seed surface. The two popular types of cotton are Red silk cotton and white silk cotton.