After birth, red blood cells are normally produced in which location?

• A. Liver
• B. Spleen
• C. Thymus
• D. Bone marrow

Answer: (D)

Verified step by step guidance

1. Understand the function of red blood cells (RBCs): Red blood cells are responsible for transporting oxygen throughout the body using hemoglobin. They are produced through a process called hematopoiesis.
2. Learn about the primary site of hematopoiesis after birth: While several organs contribute to blood cell production during fetal development, the bone marrow becomes the primary site of red blood cell production after birth.
3. Review the roles of the other options: The liver and spleen are involved in blood cell production during fetal development, but their roles diminish after birth. The thymus is primarily involved in the maturation of T-cells, a type of white blood cell, and not red blood cells.
4. Connect the information: After birth, the bone marrow takes over as the main site for producing red blood cells, replacing the liver and spleen, which were more active during fetal development.
5. Conclude: Based on the above information, the correct answer is 'Bone marrow,' as it is the primary site of red blood cell production after birth.