What is produced by the bone marrow?

The bone marrow is a vital component of the hematopoietic system, responsible for the production of various blood cells. Among these, white blood cells (WBC) play a crucial role in the immune response, helping to defend the body against infections and foreign invaders. The process of hematopoiesis occurs in the bone marrow, where stem cells differentiate into various types of blood cells, including red blood cells, platelets, and different classes of white blood cells, such as lymphocytes and neutrophils.

While platelets and components of plasma are indeed associated with blood formation, the specific mention of white blood cells highlights their pivotal role in immunity, making that choice particularly significant in the context of the question. Adrenaline is produced by the adrenal glands and is involved in the body’s stress response. Insulin, on the other hand, is produced by the pancreas and is essential for glucose metabolism. Thus, the focus on white blood cells underscores the unique and critical function of the bone marrow in supporting the immune system.