Life span of RBC is :

Options

A. 50 days
B. 70 days
C. 120 days
D. 220 days

Answer

**Step-by-Step Solution:**

1. **Understanding RBCs**: Red Blood Cells (RBCs), also known as erythrocytes, are the most abundant cells in blood. They play a crucial role in transporting respiratory gases, primarily oxygen and carbon dioxide.

2. **Formation of RBCs**: In adults, RBCs are formed in the bone marrow. This is an essential aspect of their lifecycle, as the bone marrow is responsible for producing new blood cells.

3. **Characteristics of Mammalian RBCs**: Unlike many other cells in the body, mature mammalian RBCs do not contain a nucleus. They are also characterized by their bi-concave shape, which increases their surface area for gas exchange.

4. **Lifespan of RBCs**: The average lifespan of RBCs is approximately 120 days. After this period, they undergo senescence (aging) and are removed from circulation.

5. **Destruction of RBCs**: Once RBCs reach the end of their lifespan, they are primarily destroyed in the spleen, which is often referred to as the "graveyard" of RBCs. The spleen filters the blood and removes old or damaged cells.

6. **Conclusion**: Based on the information provided, the correct answer to the question regarding the lifespan of RBCs is 120 days.

**Final Answer**: The lifespan of RBCs is 120 days.

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