or myeloid tissue
Soft, gelatinous tissue that fills bone cavities.
Red bone marrow contains stem cells, progenitor cells, percursor cells, and functional blood cells (see reticuloendothelial system ). Lymphocyte s mature in the lymphoid organs (see lymphoid tissue ). All other blood-cell formation occurs in red marrow, which also takes part in destruction of old erythrocyte s (red blood cells). Yellow bone marrow mainly stores fat s. Because the leukocyte s (white blood cells) produced in bone marrow are involved in immune defenses, marrow transplants can treat some types of immunodeficiency . Radiation and some anticancer drugs can damage marrow and impair immunity . Bone-marrow examination helps diagnose diseases related to blood and blood-forming organs.