Question

Given below are two statements:
Statement I: A protein is imagined as a line, the left end represented by first amino acid (C-terminal) and the right end represented by last amino acid (N-terminal).
Statement II: Adult human haemoglobin, consists of 4 subunits (two subunits of α type and two subunits of β type).
In the light of the above statements, choose the correct answer from the options given below:

• A. Both Statement I and Statement II are false.
• B. Statement I is true but Statement II is false.
• C. Statement I is false but Statement II is true
• D. Both Statement I and Statement II are true

Answer 1

The Correct Option is C

Let's analyze each statement:

Statement I: A protein is imagined as a line, the left end represented by the first amino acid (C-terminal) and the right end represented by the last amino acid (N-terminal).

In biology, proteins are indeed often visualized as chains or lines of amino acids. However, the convention is that the N-terminal (the end with the free amino group) is on the left, and the C-terminal (the end with the free carboxyl group) is on the right. Therefore, Statement I is false because it incorrectly reverses this convention.

Statement II: Adult human haemoglobin consists of 4 subunits (two subunits of α type and two subunits of β type).

This statement accurately describes the structure of human haemoglobin. Adult hemoglobin, known as HbA, is a tetramer consisting of two α-globin and two β-globin subunits. Thus, Statement II is true.

Considering the analysis of both statements, the correct conclusion is: Statement I is false but Statement II is true.

Answer 2

Statement I is false - A protein is not imagined as a line with the N-terminal (amino terminus) on the left end and the C-terminal (carboxyl terminus) on the right end. In reality, the N-terminal is on the left side, and the C-terminal is on the right side when representing the amino acid sequence of a protein.
Statement II is true -  Adult human hemoglobin consists of 4 subunits: two subunits of α-type and two subunits of β-type. These subunits come together to form a complex protein structure responsible for carrying oxygen in the blood.

The correct option is (C): Statement I is false but Statement II is true