Question

when do chromatin threads appear as chromosomes in the nucleus? what are they made of? Also, name the functional unit of chromosomes.

Answer 1

 Chromatin is composed of DNA and histones that are packaged into thin, stringy fibers. These chromatin fibers are not condensed but can exist in either a compact form (heterochromatin) or less compact form (euchromatin).

Gene is the functional unit of chromosome.