1. Skeletal System

2. Functions of the Skeletal System
Gives body shape and support
Protects internal organs
Allows body movement
Forms blood cells
Stores fats and minerals
There are a total of 206 bones in the human body!

3. Structure of a bone (cont.)
Compact bone- very dense; forms surface of bones
Spongy bone- less dense; forms interior of bones

4. Structure of a bone

5. Structure of a bone (cont.)
Bone marrow is the soft tissue found inside bones. There are two types:
-Red marrow: where blood cells are produced
-Yellow marrow: stores fat cells

6. Skeleton Organization

7. Axial skeletal-the central part of the skeleton, which includes the cranium, the spinal column, and the ribs
Appendicular skeleton-the bones of the skeleton that function to allow movement, such as arm and leg bones

8. Joints Joints are where bones meet. There are several types of joints:
-Immovable joints do not allow movement (cranial bones and breastbone)
-Movable joints allow movement:
-hinge joints (elbows, knees, fingers)
-ball-and-socket joint (shoulders, hips)
-pivot joints (neck)
-gliding joints (backbone)

9. Joints (cont.)
Hinge joint

10. Joints (cont.)
Ball-and-socket joint

11. Joints (cont.)
Ball-and-socket joint

12. Joints (cont.)
Pivot joint

13. Joints (cont.)
Gliding Joint

14. Joints (cont.) Ligaments-connects bones to each other
Cartilage-flexible, rubbery substance that cushions our joints

15. The skeleton changes
Infancy-skull grows as the brain grows

16. The skeleton changes (cont.)
Childhood-bone growth occurs at growth plates

17. The skeleton changes (cont.)
Adolescence-bones stop growing and growth plate hardens

18. The skeleton changes (cont.)
Adulthood-older bones break down and new bone cells develop, but more bone is broken down than is regenerated

19. Osteoporosis

21. **The foot has 26 bones, the hand has 27 = 106 bones in hands and feet!

22. References http://members.aol.com/Attic21/Anatomy/skeleton1.html