Bone marrow

Bone marrow is a type of tissue that can be found in hollow bones of many animals. In humans, it is soft, spongy tissue where blood stem cells live. Blood stem cells produce all your essential blood cells, such as red blood cells to carry oxygen and white blood cells to fight infection^[1] like a factory produces things. Bone marrow makes up about 4% of an adult human's weight (about 2.6 kilograms).

There are some diseases, like some forms of leukaemia, which stop the factory from working properly. For patients with diseases like these, the best hope of a cure is receiving a stem cell transplant.^[1]

1. ↑ ^{1.0 1.1} "Home". British Bone Marrow Registry - NHS Blood and Transplant. Retrieved 2024-05-25.