What are morphological sructure of cotton?

Answer 1

Yarn structure for cotton is the same as the structure for all yarn. Fibers -- from whatever source, except silk, are aligned so that they all run more or less parallel to each other. The process is called carding: this produces roving.

Then the roving is spun into yarn. All fibres are now running more or less parallel to each other and twisted/ twirled together to make the yarn.