Question

How many peptide bonds does each antibody molecule have?

• A. Six
• B. Four
• C. Two
• D. One

Hint:

Antibodies are Y-shaped proteins with two heavy and two light chains connected by four peptide (disulfide) bonds.

Answer 1

The Correct Option is B

Step 1: Understanding antibody structure.
An antibody (immunoglobulin) molecule is a Y-shaped protein consisting of two identical heavy chains and two identical light chains. These chains are held together by peptide (disulfide) bonds.

Step 2: Number of bonds.
There are four peptide bonds (disulfide bridges) in each antibody molecule: - Two bonds connect each light chain to a heavy chain.
- Two bonds connect the heavy chains to each other.

Step 3: Conclusion.
The correct answer is (B) Four, as each antibody molecule has four peptide (disulfide) bonds linking its chains.