Directly stimulates red blood cell production. Select one: O A. Thyroxine Ο Β. ΕΡΟ OC. Vitamin B12 D. Intrinsic factor OE. GH
The Correct Answer and Explanation is:
The correct answer is B. EPO (Erythropoietin).
Explanation:
Erythropoietin (EPO) is a hormone that directly stimulates the production of red blood cells (RBCs) in the bone marrow. It is primarily produced by the kidneys in response to low oxygen levels in the blood. When the oxygen levels in the bloodstream are insufficient (a condition known as hypoxia), the kidneys secrete EPO into the bloodstream. This hormone then stimulates the erythroid progenitor cells in the bone marrow to differentiate into red blood cells, thereby increasing the number of RBCs and improving the oxygen-carrying capacity of the blood.
EPO plays a critical role in maintaining homeostasis in the body by ensuring that an adequate number of red blood cells are present, particularly during periods of oxygen deprivation, such as at high altitudes or in cases of anemia.
Why the other options are incorrect:
- A. Thyroxine (T4): Thyroxine is a hormone produced by the thyroid gland that plays a role in regulating metabolism and growth. While thyroid hormones can indirectly affect red blood cell production by influencing overall metabolic processes, they do not directly stimulate RBC production.
- C. Vitamin B12: Vitamin B12 is essential for the proper maturation of red blood cells. It helps in DNA synthesis within the bone marrow. A deficiency in Vitamin B12 can lead to megaloblastic anemia, but it does not directly stimulate RBC production.
- D. Intrinsic factor: Intrinsic factor is a glycoprotein produced by cells in the stomach lining. It is required for the absorption of Vitamin B12 in the intestines, which is necessary for red blood cell production. However, it does not directly stimulate RBC production.
- E. GH (Growth Hormone): Growth hormone, produced by the pituitary gland, is responsible for stimulating growth, protein synthesis, and overall tissue development. While it can indirectly affect red blood cell production by promoting tissue growth and regeneration, it does not directly stimulate the production of RBCs.
In summary, Erythropoietin (EPO) is the key hormone that directly stimulates red blood cell production.
