GATE IN 2023 | GA Question: 8

Question

The information contained in DNA is used to synthesize proteins that are necessary for the functioning of life. DNA is composed of four nucleotides: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). The information contained in DNA can then be thought of as a sequence of these four nucleotides: A, T, C, and G. DNA has coding and non-coding regions. Coding regions-where the sequence of these nucleotides are read in groups of three to produce individual amino acids - constitute only about $2 \%$ of human DNA. For example, the triplet of nucleotides CCG codes for the amino acid glycine, while the triplet GGA codes for the amino acid proline. Multiple amino acids are then assembled to form a protein.

Based only on the information provided above, which of the following statements can be logically inferred with certainty?

1. The majority of human DNA has no role in the synthesis of proteins.
2. The function of about $98 \%$ of human DNA is not understood.

• A. only (i)
• B. only (ii)
• C. both (i) and (ii)
• D. neither (i) nor (ii)

Answer 1

500. The above passage describes the coding region in detail which constitute only 2% of human DNA. But that doesn’t mean that the rest 98% (non-coding region) don’t play any role in the synthesis of proteins. The details are absent here, doesn’t mean that functions are not yet discovered in the medical domain. 

Answer 2

The majority of human DNA has no role in the synthesis of proteins: This statement is true and can be directly inferred from the passage. It explicitly states that coding regions, responsible for protein synthesis, constitute only 2% of human DNA. Therefore, the remaining 98% must have other functions or no known function at this time.

(ii) The function of about 98% of human DNA is not understood: This statement is not necessarily true. While the passage mentions that the function of most of human DNA is not yet understood, it doesn't guarantee that it has no function at all. There might be roles for non-coding DNA that are still being discovered and researched. The information only emphasizes the lack of current understanding, not the absence of any potential function