Where in the body is blood produced?

Where in the body is blood produced? Blood is produced primarily in red bone marrow.

Red bone marrow contains hematopoietic stem cells, which develop into red blood cells, white blood cells, and platelets. This ongoing process is called hematopoiesis.

In adults, active red marrow is concentrated mainly in the pelvis, vertebrae, ribs, sternum, skull, and parts of the shoulder blades and long bones. Yellow marrow stores fat and can sometimes convert back to red marrow when blood production must increase.

The answer “bones” is broadly related because marrow is located inside bones, but it is imprecise. The specific tissue responsible for producing most blood cells is red bone marrow.