B- and T-cells required for immune system are produced in

Options

A. Bone marrow
B. Liver
C. Spleen
D. Lymph nodes.

Answer

**Step-by-Step Solution:**

1. **Understanding the Immune System**: The immune system is composed of various types of cells that help protect the body from infections and diseases. Among these cells, B-cells and T-cells play crucial roles.

2. **Identifying the Origin of B-cells and T-cells**: Both B-cells and T-cells are types of white blood cells (WBCs), which are essential components of the immune system.

3. **Production of White Blood Cells**: White blood cells, including B-cells and T-cells, are produced in the bone marrow. The bone marrow is a spongy tissue found in the center of bones.

4. **Differentiation of White Blood Cells**: White blood cells can be classified into two main categories: granular and agranular. Granular leukocytes include neutrophils, basophils, and eosinophils, while agranular leukocytes include lymphocytes, which consist of B-cells and T-cells.

5. **Conclusion**: Since both B-cells and T-cells are classified under agranular leukocytes and are produced in the bone marrow, the correct answer to the question is that B-cells and T-cells are produced in the bone marrow.

**Final Answer**: B- and T-cells required for the immune system are produced in the bone marrow.

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