Human Body Systems Notes Skeletal System

The Skeletal System 1. The skeletal system is all of the bones in the human body. At birth the skeleton contains about 350 bones. The adult skeleton has only 206 bones. Of these 29 are in the skull, 26 in the backbone, 25 in the sternum & ribs, 64 in the shoulders, arms and hands and 62 in the pelvis, legs and feet.

Parts of the Skeletal System Compact bone is the hard strong layer of bone. Spongy bone is found at the ends of long bones and has open spaces in it to make it light weight. Large bones are hollow and are filled with bone marrow. Bone marrow produces red blood cells. A smooth thick layer of tissue called cartilage cushions the bones from each other and reduces friction. A ligament is a band of tissue that holds bones together at the joints.

Functions of the skeletal system The skeletal system has 5 major functions. 1. Shapes and supports the body. 2. Protects the internal organs. 3. Allows movement 4. Produces blood cells (marrow) 5. Stores minerals (calcium and phosphorus)

The Skeletal System works with… The muscular system to allow movement.