Which of the following plasma proteins act as antibodies ?

Options

A. serum albumins
B. `alpha` globulin
C. `beta` globulin
D. `gamma` globulin

Answer

To determine which plasma proteins act as antibodies, we will analyze each of the options provided:

1. **Serum Albumins**:
- These proteins primarily help maintain osmotic pressure between blood vessels and tissues. They are crucial for the transport of various substances but do not function as antibodies.

2. **Alpha Globulins**:
- Alpha globulins are transport proteins in the body. They play a role in transporting various molecules but do not act as antibodies.

3. **Beta Globulins**:
- Similar to alpha globulins, beta globulins also serve as transport proteins. They are involved in the transport of substances in the blood but are not involved in the immune response as antibodies.

4. **Gamma Globulins**:
- Some gamma globulins are immunoglobulins, which are crucial for the immune response. They play a significant role in both natural and acquired immunity and are responsible for the production of antibodies against various antigens. Therefore, gamma globulins are the plasma proteins that act as antibodies.

**Conclusion**: The plasma proteins that act as antibodies are **Gamma Globulins**.

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