Blood production —The marrow, located within the medullary cavity of long bones and the interstices of cancellous bone, produces blood cells in a process called haematopoiesis.
This ends up causing new bone formation and the medullary cavites of the skull can expand outward, which causes enlarged cheeks and a " hair-on-end" appearance on skull x-ray.
与骨组织中的管腔
的（包括中央管）。
称这些空间为
是红细胞的
源地，位于我
形成，及颅
征”。
