How many types of antibodies are seen in the human body

Options

A. 5
B. 6
C. 8
D. 4

Answer

**Step-by-Step Text Solution:**

1. **Understanding Antibodies**: Antibodies are proteins produced by the immune system in response to antigens, which are substances that the body recognizes as foreign, such as pathogens.

2. **Types of Antibodies**: In the human body, there are five main types of antibodies, also known as immunoglobulins. These are:
- **IgG**: The most abundant type, making up about 70-75% of the antibodies in the blood. It can cross the placenta, providing immunity to the fetus.
- **IgA**: Found in mucosal areas, such as the gut and respiratory tract, and is also present in colostrum (the first milk produced after childbirth). It constitutes about 10-15% of the antibodies.
- **IgM**: The first antibody produced in response to an infection, accounting for about 5-10% of the total antibodies.
- **IgE**: Involved in allergic reactions and responses to parasitic infections, it is present in very low amounts, approximately 0.1%.
- **IgD**: The least understood antibody, it is present in small amounts (about 0.2%) and is believed to play a role in the initiation of immune responses.

3. **Conclusion**: Therefore, the total number of types of antibodies present in the human body is five.

**Final Answer**: There are five types of antibodies in the human body: IgG, IgA, IgM, IgE, and IgD.

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