Bone marrow
Bone marrow is the tissue comprising the center of large bones. It is the place where new blood cells are produced. Bone marrow contains stem cells which produce three types of blood cells: leukocytes, red blood cells, and platelets.
"Long bones" are tubular in structure, and the hollow middle is filled with yellow marrow. While the majority of long bones are formed of cortical ("compact") material; at the ends are the epiphysis, which are generally composed of cancellous ("spongy") material and red marrow.
Bone marrow as a food
Bone marrow has recently fallen out of favor as a food, commonly now being used only as a flavoring for soup. Bone marrow is a source of protein and high in monounsaturated fats. These fats are known to decrease LDL cholesterol levels. Some believe this results in a reduced risk of coronary heart disease, prompting them to make bone marrow a dietary staple.
See also
Bone marrow as a food: