Types of Cotton

Cotton --- the seed hair of a wide variety plants of the Gossypium family is called cotton.

There have many varieties botanical name of cotton-- Gossypium herbaceum, Gossypium arboreum, Gossypium hirsutum, Gossypium barbadense.

Structure View of Cotton Fiber:-- sectional view of cotton.png

The cotton fiber is a single plant cell. It cross section is oval, compared with the normal hexagonal plant cell. However, like all plant cell cotton has the following:

Cuticle, Primary cell, Secondary cell and Lumen

The cuticle is the very outside or skin of cotton fiber. It is composed of a waxy layer only a few molecular thick. The waxy nature of the cuticle enables it to adhere tenaciously to the primary wall of the fiber .

The primary cell wall is immediately underneath the cuticle , is about 200 nm thick . It is composed of very fine threads of cellulose called fibrils.

Secondary cell--
beneath the primary cell wall lies the secondary cell wall which forms the bulk of the fiber. Concentric layers of spiraling , cellulosic fibers, not unlike the growth rings of trees , make up the secondary wall. The more thick of this layer means more matured fiber, and more thin of this layer means more immature fiber.

Lumen-- The hollow canal running the length of the fiber is called the lumen. Its wall are the innermost , concentric layer of spirals of the secondary cell wall. The lumen was once the central vacuole of the growing cotton fibers.