Question

Regarding the assertion and reason; choose the correct option.

Assertion [A] : All living organisms contain 20 types of amino acids and 5 nucleotides.

Reason [R] :The living cells contain A, G, C, T and U nitrogenous bases.

• A. Assertion [A] is True and Reason [R] is False.
• B. Reason [R] is True and Assertion [A] is False.
• C. Assertion [A] is True and Reason [R] is True and is a correct explanation for [A].
• D. Assertion [A] is True and Reason [R] is True but it does not explain [A].

Answer 1

The correct option is D Assertion [A] is True and Reason [R] is True but it does not explain [A].

All living organisms have 20 amino acids and 5 nitrogenous bases - Adenine, Guanine, Cytosine, Thymine and Uracil. These nitrogen bases combine with a molecule of sugar and one or more phosphate groups to form nucleotides, thus forming 5 types of nucleotides- Adenosine triphosphate, Guanosine triphosphate, Cytosine triphosphate, Thymidine triphosphate and Uridine triphosphate.
The 5 nitrogenous bases however have no co-relation to the number of amino acids in living organisms and therefore [R] does not explain [A].