Which organ is considered as "Graveyard of RBC" where most of them are destroyed by macrophages and called as "blood bank"

Options

A. (a) Lungs
B. (b) Heart
C. (c) Liver
D. (d) Spleen

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for an organ that is referred to as the "graveyard of RBC" where red blood cells (RBCs) are destroyed by macrophages and is also known as a "blood bank."

2. **Identifying the Characteristics of the Organ:**
- The organ in question is responsible for the destruction of old and damaged RBCs.
- It uses macrophages, which are a type of white blood cell, to carry out this destruction.
- This organ also plays a role in filtering blood and replenishing new RBCs.

3. **Functions of the Organ:**
- It produces lymphocytes, which are essential for the immune response.
- It is considered the largest lymphoid organ in the body.
- It acts as a reserve for blood cells, which can be crucial during emergencies such as hemorrhagic shock.

4. **Conclusion:** Based on the characteristics and functions described, the organ that fits all these criteria is the **spleen**. Therefore, the correct answer is the spleen.

**Final Answer:** The organ considered as the "graveyard of RBC" and known as a "blood bank" is the **spleen**.

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