AEMCA Practice Exam

What is a hemocytoblast?

1. A type of red blood cell

2. A cell that forms blood elements

3. A type of white blood cell

4. A cell involved in blood clotting

The correct answer is: A cell that forms blood elements

A hemocytoblast is a type of stem cell that is responsible for the formation of various blood elements, including red blood cells, white blood cells, and platelets. It is an undifferentiated progenitor cell located primarily in the bone marrow. Hemocytoblasts are critical in the process of hematopoiesis, which is the formation of blood cellular components. They can differentiate into myeloid or lymphoid lineages, leading to the production of different types of blood cells required for various functions in the body. The other options do not correctly represent the role of a hemocytoblast. While red blood cells and white blood cells are derived from hemocytoblasts, these specific cells are the final forms that perform particular functions within the bloodstream rather than the precursor cell itself. Additionally, a cell involved in blood clotting refers to platelets, which are also produced from hemocytoblasts but do not accurately describe the hemocytoblast's broader role in blood element formation. Thus, identifying hemocytoblasts as cells that form blood elements accurately captures their essential function in the circulatory system.