Immunoglobulins (antibodies) of the blood plasma are

Options

A. glycoproteins
B. lipoproteins
C. flavoproteins
D. all of these

Answer

**Step-by-Step Solution:**

1. **Definition of Immunoglobulins:** Immunoglobulins, commonly known as antibodies, are specialized proteins found in blood plasma that play a crucial role in the immune response.

2. **Chemical Nature:** The primary chemical nature of immunoglobulins is that they are glycoprotein molecules. This means they consist of protein and carbohydrate components.

3. **Production:** Immunoglobulins are produced by plasma cells, which are a type of white blood cell. These cells are responsible for generating antibodies in response to antigens.

4. **Function in Immune Response:** The main function of immunoglobulins is to act as a critical part of the immune response. They recognize and bind to specific antigens, which can be pathogens like bacteria or viruses.

5. **Mechanism of Action:** Once the immunoglobulins recognize an antigen, they bind to it. This binding leads to the destruction of the antigen, effectively neutralizing the threat posed by the pathogen.

6. **Conclusion:** Therefore, immunoglobulins (antibodies) of blood plasma are classified as glycoproteins, which are produced by plasma cells and are essential for the immune response.

**Final Answer:** Immunoglobulins (antibodies) of the blood plasma are glycoproteins.

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