Which of the following elements is important to maintain structure of immunoglobulin

Options

A. P
B. S
C. Fe
D. Ca

Answer

To answer the question "Which of the following elements is important to maintain the structure of immunoglobulin?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Immunoglobulin**:
- Immunoglobulins, also known as antibodies, are composed of two heavy chains and two light chains. They have a specific structure that is crucial for their function in the immune response.

2. **Identify the Components of Immunoglobulin**:
- Immunoglobulins are glycoproteins produced by plasma cells. They consist of inter-chain and intra-chain connections that help maintain their three-dimensional structure.

3. **Recognize the Role of Disulfide Bonds**:
- Within the structure of immunoglobulins, there are disulfide bonds that form between cysteine residues. These bonds can be classified into inter-chain (connecting different chains) and intra-chain (within the same chain) disulfide bonds.

4. **Determine the Element Responsible for Disulfide Bonds**:
- Disulfide bonds are formed by the oxidation of two cysteine amino acids, which contain sulfur. Therefore, sulfur is the key element that contributes to the formation of these bonds.

5. **Conclude the Importance of Sulfur**:
- Since sulfur is essential for the formation of disulfide bonds that stabilize the structure of immunoglobulins, it is the correct answer to the question.

### Final Answer:
The element important to maintain the structure of immunoglobulin is **sulfur**.

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