Antiserum contains

Options

A. Antigen
B. Leucocytes
C. Antibodies
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Antiserum**: Antiserum is a serum derived from the blood of an animal that has been exposed to a specific antigen. It is important to know what antiserum is before determining its contents.

2. **Role of Antigens**: An antigen is a substance that triggers an immune response in the body. It can be a pathogen that causes disease. When an organism is exposed to an antigen, it activates the immune system.

3. **Immune Response**: In response to the presence of an antigen, the immune system produces antibodies. These antibodies are proteins that specifically target and neutralize the antigen.

4. **Composition of Antiserum**: Since antiserum is obtained from the serum of an animal that has been exposed to an antigen, it primarily contains antibodies that have been generated in response to that antigen.

5. **Evaluating the Options**:
- **Antigen**: Incorrect, as antiserum does not contain the antigen itself; it contains the body's response to it.
- **Leukocytes**: Incorrect, as leukocytes (white blood cells) are part of the immune system but are not the primary component of antiserum.
- **Antibodies**: Correct, because antiserum is rich in antibodies that target the specific antigen the animal was exposed to.
- **None of these**: Incorrect, as we have identified that antiserum contains antibodies.

6. **Conclusion**: The correct answer to the question "Antiserum contains" is **antibodies**.

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