In a typical antibody, disulphide bonds are not seen in which of the following?

Options

A. between heavy chain and light chain
B. between two heavy chains
C. between two light chains
D. within the heavy chain

Answer

To solve the question, "In a typical antibody, disulphide bonds are not seen in which of the following?", we need to analyze the structure of antibodies and the presence of disulfide bonds in their composition.

### Step-by-Step Solution:

1. **Understand the Structure of Antibodies**:
- Antibodies, also known as immunoglobulins, are composed of four polypeptide chains: two heavy chains and two light chains.
- The heavy chains are typically longer and have more amino acids than the light chains.

2. **Identify the Types of Bonds**:
- Disulfide bonds (or linkages) are covalent bonds that form between the sulfur atoms of cysteine residues in proteins.
- In antibodies, disulfide bonds can occur:
- Between heavy chains and light chains.
- Between two heavy chains.
- Within a heavy chain (intrachain).
- Within a light chain (intrachain).

3. **Analyze Each Option**:
- **Between heavy chain and light chain**: Disulfide bonds are present here, connecting the heavy chains to the light chains.
- **Between two heavy chains**: Disulfide bonds are also present here, linking the two heavy chains together.
- **Between two light chains**: This is the key point. There are no disulfide bonds between the two light chains; they are connected to the heavy chains but not to each other.
- **Within heavy chain**: Disulfide bonds are present within the heavy chain, linking different parts of the same chain.

4. **Conclusion**:
- The option that correctly identifies where disulfide bonds are not seen is **between two light chains**.

### Final Answer:
Disulfide bonds are not seen **between two light chains**.