29. Assertion : DNA is associated with proteins. Reason : DNA binds around histone proteins that form a pool and the entire structure is called a nucleosome.

(a)       If both the assertion and the reason are true and the reason is a correct explanation of the assertion

(b)       If both the assertion and reason are true but the reason is not a correct explanation of the assertion 

(c)        If the assertion is true but the reason is false

(d)       If both the assertion and reason are false

(e)       If the assertion is false but reason is true

Ans. (a) A chain of DNA has 140 base pairs, make 7/4 turns and twist around a histone octamer forming nucleosome. The core of nucleosome consists of 4 histones and H2A,H2B,H3 and H4.