Major content provider: U.S. National Cancer
Skeletal System: Unit Review
Here is what we have learned from this unit:
- The human skeleton is well adapted for the functions it must perform. Functions of bones include support, protection, movement, mineral storage, and formation of blood cells.
- There are two types of bone tissue: compact and spongy. Compact bone consists of closely packed osteons, or haversian system. Spongy bone consists of plates of bone, called trabeculae, around irregular spaces that contain red bone marrow.
- Osteogenesis is the process of bone formation. Three types of cells, osteoblasts, osteocytes, and osteoclasts, are involved in bone formation and remodeling.
- In intramembranous ossification, connective tissue membranes are replaced by bone. This process occurs in the flat bones of the skull. In endochondral ossification, bone tissue replaces hyaline cartilage models. Most bones are formed in this manner.
- Bones grow in length at the epiphyseal plate between the diaphysis and the epiphysis. When the epiphyseal plate completely ossifies, bones no longer increase in length.
- Bones may be classified as long, short, flat, or irregular. The diaphysis of a long bone is the central shaft. There is an epiphysis at each end of the diaphysis.
- The adult human skeleton usually consists of 206 named bones and these bones can be grouped in two divisions: axial skeleton and appendicular skeleton.
- The bones of the skeleton are grouped in two divisions: axial skeleton and appendicular skeleton.
- There are three types of joints in terms of the amount of movement they allow: synarthroses (immovable), amphiarthroses (slightly movable), and diarthroses (freely movable).