The Probert Encyclopaedia of Medicine

MARROW

The marrow (also called medullary) cavity is the region within the bone which houses the marrow, responsible for generation of blood cells. The marrow in newborns and children is generally red, turning yellow in adults in all bones with the exceptions of upper ends of the humerus and femur and in many of the flat bones of the skull, vertebrae, ribs, sternum, and hip. The red marrow, also known as myeloid tissue, produces all types of blood cells except for lymphocytes and monocytes (which are formed primarily in the lymph nodes and the spleen) . Anemia is a disease in which the myeloid tissue cannot produce sufficient red blood cells (as when the body does not get enough of the mineral iron), with the chief symptom being chronic fatigue.
Research Marrow