How does erythropoietin (EPO) regulate red blood cell production?

• A. EPO converts white blood cells into red blood cells.
• B. EPO stimulates the bone marrow to produce more red blood cells.
• C. EPO breaks down old red blood cells in the liver.
• D. EPO decreases the lifespan of red blood cells.

Answer: (B)

Verified step by step guidance

1. Understand the role of erythropoietin (EPO): EPO is a hormone primarily produced by the kidneys in response to low oxygen levels in the blood.
2. Recognize the target of EPO: EPO acts on the bone marrow, which is the primary site of red blood cell (RBC) production.
3. Identify the effect of EPO on the bone marrow: EPO stimulates the bone marrow to increase the production of red blood cells, thereby enhancing the oxygen-carrying capacity of the blood.
4. Clarify misconceptions: EPO does not convert white blood cells into red blood cells, nor does it break down old red blood cells in the liver or decrease their lifespan.
5. Summarize the correct function: EPO's main function is to stimulate the bone marrow to produce more red blood cells in response to hypoxia (low oxygen levels).