Question

Assertion :Histones are basic proteins of major importance in packaging of eukaryotic DNA. DNA and histones comprise chromatin forming the bulk of eukaryotic chromosome. Reason: Histones are of five major types: $H_1,H_{2}A,H_{2}B,H_3$ and $H_4$.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

Answer: (A)

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
Histones are basic proteins of major importance in the packaging of eukaryotic DNA, DNA and histones together comprise chromatin, forming the bulk of the eukaryotic chromosome. Histones are made up of five major types, $H_1,H_{2}A$, and $H_{2}B$ are lysine rich. $H_3$ and $H_4$ arginine-rich, $H_1$ units link neighboring nucleosomes while the others are elements of nucleosome structure. Histone proteins are synthesized during the S-phase when DNA synthesis occurs.

Therefore, the correct answer is option A.