Number of proteins belonging to complement system is

Options

A. 6
B. 18
C. 24
D. 30

Answer

To solve the question regarding the number of proteins belonging to the complement system, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Complement System**:
- The complement system is an essential part of the immune system. It consists of a series of proteins that work together to enhance the ability of antibodies and phagocytic cells to clear pathogens and damaged cells.

2. **Identifying the Role of Complement Proteins**:
- These proteins play a crucial role in promoting inflammation and attacking the plasma membranes of pathogens. This indicates that they are vital for the immune response.

3. **Counting the Proteins**:
- It is known that the complement system comprises more than 30 proteins. These proteins can be found in two forms:
- Soluble proteins that circulate in the blood.
- Membrane-associated proteins that are found on the surfaces of cells.

4. **Choosing the Correct Option**:
- Given the options: 6, 18, 24, or 30, we can conclude that since the complement system has more than 30 proteins, the correct answer is **30** (option D).

### Final Answer:
The number of proteins belonging to the complement system is **30**.

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