Bone-marrow is a soft, fatty tissue found inside of bones that produces blood cells (red blood cells, white blood cells, and platelets). Red blood cells carry oxygen throughout the body. White blood cells act to ward off infection. Platelets aid in blood-clotting.
Update Date 3/28/2014
Updated by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.