What are the structure of Chromosomes, Types and its Functions?

This article gives the basic concept on What is the Chromosome Structure and the function? According to Cohn (1964), the term chromatin refers to the Feulgen positive materials observed in the interphase nucleus and later during the division of the cell nucleus. they are long, fine thread-like structures 40 to 150 A0 in diameter.  Ris (1969) has observed that chromatin fibres contain only single DNA molecule. The term chromosome was coined by W.Waldever in 1888.