HB+Skeletal+System

=Skeletal System=

A bone is an organ composed of what types of tissues?

 * Bones are organs of the skeletal system. The tissues of the system are compact and spongy bone, various types of cartilage, and fibrous connective tissue in the ligaments that hold bones together.

Describe the make up of LONG bone.

 * The long bone has a hyaline cartilage that covers the ends of the long bone. Periosteum, fibrous connective tissue, covers the rest of the bone. The spongy bone which contains red blood marrow is in the epiphyses. The yellow bone marrow is in the medullary cavity of the diaphysis. The compact bone makes up the wall of the diaphysis.

What types of cells are involved in bone growth, remodeling, and repair?

 * Some cells involved in growth, remodeling and repair of the bone are osteoblasts, which are bone-forming cells. Osteocytes, which are mature bone cells derived from osteoblasts, and osteoclasts which break down and obsorb bone.

What are two types of ossification?

 * Intramembranous Ossification: bones develop between sheets of fibrous connective tissue. Examples are flat bones such as bones of the skull.
 * Endochondral Ossification: Cartilaginous models of the bones are replaced by calcified bone matrix.

What are the four steps required in fracture repair?

 * Repairing fracture requires hemotoma formation, fibrocartilaginous callus, bony callus and remodeling.

What are the functions of the skeleton?

 * **Support** - the body is kept in position by the muscles that attach to the skeleton.
 * **Protection**- the flat bones protect the internal organs.
 * **Movement** - provided by the joints
 * **Production of Blood** - blood cells are produced in the red bone marrow in the centre of some bones, including the pelvis, ribs, vertebrae and stenum. The yellow bone marrow stores fat. The yellow bone marrow can convert to red bone marrow if the body needs additional blood production.
 * **Storage -** Minerals are stored in the bone, mostly calcium and phosphorus.

How are joints classified?

 * Bones are classified in articulations of fibrous joints, cartilaginous joints, and synovial joints.

Give examples of different types of synovial joints and the movements they permit.

 * Synovial Joints permit felxion and extension, adduction and abduction, rotation and circumduction, and inversion and eversion.