Question

Cotton is obtained from
(a) Epidermal tissue system
(b) Ground tissue system
(c) Vascular tissue system
(d) Meristematic tissue system

Answer 1

Hint: The tissue system forms the outermost covering of the plant body. It is in direct contact with the external environment. It possesses root hairs and trichomes.

Complete answer:
Cotton is obtained from the ‘Epidermal tissue system’. Cotton is a soft, fluffy staple fiber that is obtained from long unicellular epidermal hair or lint (fuzz) of Gossypium seeds. A single seed can possess up to 1000 lint hair. One kilogram of cotton comprises over 200 million hairs. These hairs have cellulose thickening.
The Epidermal tissue system comprises epidermal cells, Epidermal structures, i.e., stomata, and Epidermal appendages – the trichomes and hairs.
-Epidermis: It is the outermost surface of the primary plant body. It is composed of a single layer of epidermal cells. These cells are living and have cytoplasm and a nucleus. These are parenchymatous cells possessing a large central vacuole and peripheral cytoplasm lining the cell wall.
-Stomata: These are minute structures present in the epidermis of leaves. Each stoma comprises guard cells and a tiny stomatal pore. Guard cells guard the opening and closing of the stomatal pore and regulate the stomatal movement. Stomata regulate the process of transpiration and gaseous exchange.
-Epidermal appendages: These are the outgrowths from the epidermis layer. They are of two types, namely, Root hairs and Trichomes. Root hairs increase the surface area for absorption in the roots. Trichomes aid in ceasing water loss caused by transpiration.

So, the correct answer is ‘Epidermal tissue system’.

Note:
The epidermal tissue system provides protection from external injuries, excessive evaporation, etc.
-Trichomes facilitate the secretion of many sticky substances.
-Control of transpiration by stomatal apparatus, trichomes, and cuticle.
-Absorption of water and minerals by root hairs.