Haemopoiesis is the process by which mature blood cells develop from precursor cells. It continues continuously throughout embryonic and adult life and as a result new cells formed in the so-called haemopoietic regions constantly replace mature blood cells in the circulation.
In the embryo, haemopoiesis occurs at different stages in the yolk sac, the liver, the spleen, lymph nodes and the bone marrow. In the adult, erythrocytes, granulocytes, monocytes and platelets are formed in the bone marrow while the lymphocytes are formed mainly in the lymph nodes, spleen, thymus and lymphatic nodules of the gastrointestinal tract. However, the lymphocytes present in these organs originate directly or indirectly from the bone marrow.
Question. Which bones contain haemopoietic marrow?