AEMCA Practice Exam

Where does haematopoiesis primarily occur in infants?

1. In the skull

2. In the red bone marrow of long bones

3. In the pelvis

4. In the vertebral column

The correct answer is: In the red bone marrow of long bones

Haematopoiesis, the process of blood cell formation, primarily occurs in the red bone marrow in infants. At this stage of development, the red bone marrow is abundantly active in producing various types of blood cells including red blood cells, white blood cells, and platelets. In infants, this process is critical as their bodies are rapidly growing and require a heightened production of blood cells to support metabolic, immune, and overall physiological functions. While other anatomical sites such as the skull, pelvis, and vertebral column do contribute to haematopoiesis, they play a lesser role in infants compared to the red bone marrow of long bones. As individuals age, the sites of haematopoiesis shift to include more central locations such as the pelvis and vertebral column, but in infants, the red bone marrow in long bones remains the primary site of blood cell production.