Question: What part of cotton is used for making the fibre? 

Answer: Cotton fiber (once processed to remove seeds and traces of wax, protein, etc.) consists of nearly pure cellulose, a natural polymer. Cotton production is very efficient, in the sense that, ten percent or less of the weight is lost in subsequent processing to convert the raw cotton bolls into pure fiber. The cellulose is arranged in a way that gives cotton fibers a high degree of strength, durability, and absorbency. Each fibre is made up of twenty to thirty layers of cellulose coiled in a neat series of natural springs. When the cotton boll (seed case) is opened the fibres dry into flat, twisted, ribbon-like shapes and become kinked together and interlocked. This interlocked form is ideal for spinning into a fine yarn.
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