Structure and Function of Bone
The compact bone that is seen in the diagram below is the hardest bone. The layer of spongy bone which is beneath it helps to prevent the bone from being too heavy and has spaces in it. The bone marrow is in the centre of the bone structure. As the name suggests, it is very soft and it has a good blood supply. The ends of the bone are covered with cartilage which prevents friction between bones. Cartilage is much softer than bones as it is not made of as much minerals, however, like bone, it contains collagen.
The difference between the spongy bone and the compact bone is shown below.
Recall: red and white blood cells as well as platelets are made in the bone marrow.
The human skeleton has several functions:
-Support: examples –leg bones, vertebral column, pelvic girdle
-Movement: examples- leg and arm bones, vertebral column
-Protection: examples- skull, ribs, vertebral column
-Making red and white blood cells– this is done by the marrow in the leg bones and the ribs