NEET2026BiologyChapterActual
Which of the following features accurately describes a typical antibody molecule?
Options
- AIt consists of four identical polypeptide chains forming a Y-shaped structure.
- BIt is represented as H₂L₂ and the chains are interconnected by disulfide bonds.
- CThe antigen-binding sites are located at the stem region of the molecule.
- DOnly the heavy chains possess variable regions that interact with antigens.
Correct answer
B. It is represented as H₂L₂ and the chains are interconnected by disulfide bonds.
Step-by-step solution
A typical antibody molecule consists of four polypeptide chains: two identical light chains and two identical heavy chains. Therefore, it is not made of four identical chains. The molecule is represented as H₂L₂ . These chains are held together by disulfide bonds to form a Y-shaped structure. The antigen-binding sites are located at the N-terminal ends (the tips of the arms of the Y-shaped structure), not at the stem region. Both heavy and light chains possess variable regions at their N-terminals, which together f