The Skeletal System

1. The Skeletal System

2. The Skeletal System • Definition: • all the bones in the body

3. The Skeletal System Function • forms an internal, living framework that • provides shape and support • protects internal organs • moves bones • forms blood cells • stores calcium and phosphorous compounds for later use

4. Bones • Made of layers of living tissue • Covered with a tough, tight-fitting membrane called the periosteum

5. Compact Bone • Directly under the periosteum • Hard, strong layer • Gives bones strength • Contains deposits of calcium phosphate • Contains bone cells and blood vessels

6. Spongy Bone • Located at the ends of long bones • Has many small, open spaces that make bones lightweight • Filled with a substance called marrow • yellow composed of fat cells • red produces red blood cells

7. Cartilage • Smooth, slippery, thick layer of tissue • Covers the ends of bones • Does not contain blood vessels or minerals • Flexible and acts as a shock absorber • Makes movement easier by reducing friction

9. Joints • Definition: • Any place where two or more bones come together

10. Joints • Kept far enough apart by a thin layer of cartilage so that they do not rub against each other as they move • Bones are held in place at joints by a tough band of tissue called ligament

11. Types of Joints • Immovable • Skull • Pelvis • Moveable • Pivot • Ball & socket • Hinge • Gliding

12. Types of Joints • Ball and Socket Joint • Bone with a rounded end that fits into a cuplike cavity on another bone http://www.shockfamily.net/skeleton/JOINTS.HTML

13. Types of Joints • Pivot Joint • One bone rotates in a ring of another bone that does not move http://www.funhousefilms.com/b-pivot2.jpg

14. Types of Joints • Hinge Joint • Back-and-forth movement like hinges on a door http://www.shockfamily.net/skeleton/JOINTS.HTML

15. Type of Joints • Gliding Joint • One part of a bone slides over another bone http://www.shockfamily.net/skeleton/JOINTS.HTML