Leucocytes are responsible for humoral immune

Options

A. T-lumphocytes
B. B-lymphocytes
C. Macrophages
D. Neutrophils

Answer

**Step-by-Step Solution:**

1. **Understanding Leukocytes**:
- Leukocytes, also known as white blood cells (WBCs), play a crucial role in the immune response. They are involved in protecting the body against infections and foreign invaders.

2. **Types of Leukocytes**:
- The main types of leukocytes include T-lymphocytes, B-lymphocytes, macrophages, and neutrophils. Each type has a specific function in the immune response.

3. **Identifying the Role of T-Lymphocytes**:
- T-lymphocytes are primarily responsible for cell-mediated immunity. This means they do not directly produce antibodies but instead help in the activation of other immune cells.

4. **Identifying the Role of B-Lymphocytes**:
- B-lymphocytes are responsible for humoral immunity. They produce antibodies (also known as immunoglobulins) that circulate in the blood and help neutralize pathogens.

5. **Understanding Humoral Immune Response**:
- The humoral immune response is characterized by the production of antibodies by B-lymphocytes. These antibodies bind to specific antigens on pathogens, marking them for destruction.

6. **Role of Macrophages and Neutrophils**:
- Macrophages and neutrophils are involved in the cellular immune response. Macrophages can phagocytose (engulf and digest) pathogens, while neutrophils are the first responders to sites of infection.

7. **Conclusion**:
- Based on the information, the leukocytes responsible for humoral immunity are the B-lymphocytes. Therefore, the correct answer to the question is B-lymphocytes.

**Final Answer**: B-lymphocytes are responsible for humoral immune response.

---