Skeletal+System+WB

1) A bone is an organ composed of what types of tissues? (Be detailed, pictures nice) (2) Describe the make up of LONG bone. DESCRIBE (3) What types of cells are involved in bone growth, remodeling, and repair? DESCRIBE (4) What are two types of ossification. DESCRIBE. (5) What are the four steps required in fracture repair? DESCRIBE. (6) What are the functions of the skeleton? (7) How are joints classified? (8) Give examples of different types of synovial joints and the movements they permit.

1. A bone is an organ composed of main connective and fibrous tissues. 2. A long bone consists of the bone shaft, which is made of a hard, fibrous tissue. The ends of the bone, where joints are in the body, are covered in a specialized cartilage, which allows free movement of arms, legs, etc. The center of the bone is filled with bone marrow, which is spongy. 3. Osteoblasts utilize calcium secretions to form, shape, and grow bones. Osteocytes are much like osteoblasts, but help in keeping the bones strong and in the correct shape. Osteoclasts are responsible for breaking down bone matter, in order to put calcium and phosphates into the blood. 4. The two types of ossification (bone formation) are intramembraneous ossification, and endochondral ossification. Intramembraneous ossification forms bones from layers of connective tissues. Endochondral ossification begins in the hyaline cartilage in the end of bones. 5. First, a hematoma forms. A hematoma is a blood clot in the bone fracture. Next, a fibrocartilaginous callus forms in the fracture, helping to begin to put the bone back together. Then, the fibrocartilaginous callus turns to a hard, bony callus, which tightly joins the fracture back together. Finally, the osteoblasts form new bone inside the fractured area, which leaves the bone as it was before the fracture. 6. The skeleton serves to produce blood cells, supports the body, provide protection for the organs, and to give the body the ability to move. 7. Joints are classified as synovial, fibrous, or cartilaginous. 8. Synovial joints are located in the hips and shoulders, and allow movement in all direction. They are also located in the knees and elbows, but only provide movement in one direction.