Function: Formation of Blood Cells

Bone marrow, the soft fatty tissue inside bone cavities, is the source of all the red blood cells and platelets and most of the white blood cells. In adults, blood cells are formed mainly in the bone marrow of flat bones, such as the shoulder blades, ribs, breastbone, and pelvis. All the blood cells are derived from a single type of cell called a stem cell. Production of stem cells is controlled by hormones, including erythropoietin, which is produced by the kidneys; thyroid hormones; corticosteroids secreted by the adrenal glands; and growth hormones from the pituitary gland.

Cells in bone marrow

Blood cells, such as red and white cells, and fat cells are found in bone marrow. Tiny blood vessels called sinusoids supply nourishment and carry away wastes.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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