Structurally, antibody is represented as

Options

A. `H_1L_3`
B. `H_2L_2`
C. `H_2L_4`
D. `H_4L_4`

Answer

To answer the question "Structurally, antibody is represented as," we need to analyze the structure of antibodies and identify the correct representation among the given options.

### Step-by-Step Solution:

1. **Understanding Antibodies**: Antibodies are proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses. They are also known as immunoglobulins.

2. **Structure of Antibodies**: Antibodies are composed of four peptide chains. These chains are categorized into two types:
- **Heavy Chains**: There are two long chains known as heavy chains, represented as 'H'.
- **Light Chains**: There are two shorter chains known as light chains, represented as 'L'.

3. **Representation of Antibody Structure**: The typical structural representation of an antibody can be denoted as H2L2, where:
- 'H2' indicates the presence of two heavy chains.
- 'L2' indicates the presence of two light chains.

4. **Evaluating Options**: Among the options provided (H1L3, H2L2, H2L4, H4L4), we need to identify the correct representation:
- **H1L3**: Incorrect, as there is only one heavy chain and three light chains.
- **H2L2**: Correct, as it accurately represents two heavy chains and two light chains.
- **H2L4**: Incorrect, as it suggests two heavy chains and four light chains.
- **H4L4**: Incorrect, as it suggests four heavy chains and four light chains.

5. **Conclusion**: The correct structural representation of an antibody is H2L2.

### Final Answer:
The correct structural representation of an antibody is **H2L2**.

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