Question

Which of the following is not a component of DNA?

• A. Thiamine
• B. Adenine
• C. Guanine
• D. Cytosine

Answer 1

The Correct Option is A

The components of DNA include four nitrogenous bases:

Adenine (A)

Thymine (T)

Guanine (G)

Cytosine (C)

These bases pair as follows:

Adenine pairs with Thymine (A-T)

Guanine pairs with Cytosine (G-C)

Thiamine is not a component of DNA. It is a vitamin (specifically, vitamin B1) and does not appear in the structure of DNA. The correct component related to Thiamine is Thymine (which pairs with Adenine in DNA).

Thus, the correct answer is (1) Thiamine.

Answer 2

Thiamine is a vitamin (Vitamin B1) and not a nucleotide base. DNA consists of the bases adenine, guanine, cytosine, and thymine. Remembering the difference between thymine (a DNA base) and thiamine (a vitamin) is crucial in such questions.