Which provide micro-environment for the development and maturation of B-lymphocytes

Options

A. Bone-marrow
B. Spleen
C. Thymus
D. Both (1) and (3)

Answer

To answer the question "Which provides the micro-environment for the development and maturation of B-lymphocytes?", we can break down the information as follows:

### Step-by-Step Solution:

1. **Identify the Lymphoid Organs**:
- Understand that lymphoid organs are crucial for the development and maturation of lymphocytes, which include B-lymphocytes and T-lymphocytes.

2. **Differentiate Between Primary and Secondary Lymphoid Organs**:
- Primary lymphoid organs are where lymphocytes originate and mature. The two primary lymphoid organs are the bone marrow and the thymus.

3. **Role of Bone Marrow**:
- The bone marrow is a primary lymphoid organ located within the bones. It is responsible for the production of blood cells, including B-lymphocytes.
- Bone marrow provides the necessary microenvironment for the development and maturation of B-lymphocytes.

4. **Role of Thymus**:
- The thymus is another primary lymphoid organ located near the heart and beneath the breastbone.
- It is specifically involved in the maturation of T-lymphocytes, not B-lymphocytes.

5. **Conclusion**:
- Based on the information, the correct answer to the question is that the **bone marrow** provides the microenvironment for the development and maturation of B-lymphocytes.

### Final Answer:
The bone marrow provides the micro-environment for the development and maturation of B-lymphocytes.

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