The Skeletal System

1. The Skeletal System KavittaGhai, Shefali Mathrani, Rebecca Ryan

2. Main Functions • Protection & Support • Skeleton protects internal organs and fragile body tissues • Provides framework for body • Allows us to keep our shape • Blood cell formation • Red bone marrow produces red and white blood cells • Stores minerals and energy • Bone tissues stores calcium and phosphorus • When required, minerals are released into the blood • Yellow bone marrow stores chemical energy and fat • Aids movement • Works with muscular system to allow body to move

3. How It Works • Protection and Support: • Cranium protects brain and eyes • Ribs protect heart and lungs • Vertebrae protects spinal cord • Production of blood cells: • Red marrow produces blood cells, platelets and most white blood cells • Some white blood cells develop in yellow marrow • Cases of severe blood loss: body can convert yellow marrow to red marrow to increase blood cell production. • Movement: • Muscles attached to bones through tendons • Bones and muscles work together by impulses and signals • Nervous system signals muscle to contract • Muscle contracts, bone moves with it

4. What Are Bones? • Hard, whitish tissue making up the skeleton • Considered living organs • Made of epithelial tissue—the thin tissue that forms the outer layer of a body's surface, nerves, muscle tissue and connective tissue • Grow and change as your body mature

5. What Makes Up Bones • Periosteum: thin, dense membrane that lines the outer surface of bones and contains nerves and blood vessels to nourish bone • Compact Bone: smooth and very hard part of bone, blood vessels run through it • Cancellous Bone (Spongy Bone): looks like sponge because has large open spaces, not as hard as compact bone, protects bone marrow • Bone Marrow: produces blood cells and stores energy

6. Joints • Immovable Joints: connected by connective tissue, do not allow movement • Slightly Movable Joints: joined together by cartilage • Freely Movable Joints: joined by cartilage and cushioned cavities filled with synovial fluid

7. Types of Joints

8. Strengths • Muscles and bones enable body to move • Bones are strong because of calcium compounds • Marrow produces new blood cells and repairs old ones • Comprise only 18% of body weight

9. Weaknesses • Arthritis: disease of the joints, caused by destruction of cartilage between bones and joints • Scoliosis: abnormal curvature of the backbone, caused by disease that affects spine • Osteoporosis: disease of the bone, becomes thin so easy to fracture

10. Cures • Arthritis: Lifestyle changes, physical therapy, medication, and surgery • Scoliosis: braces or surgery • Osteoporosis: Proper diet, adequate calcium, medication, exercising

11. Weaknesses Cont. • Fractures: bone shatters • Torn ligaments: breakage of connective tissue which holds together bones and joints

12. Maintaining A Healthy Skeleton • Drink milk or take calcium supplements • Exercise; engage in weight-lifting • Maintain a healthy diet; orange juice, broccoli, fish, etc. • Keep teeth clean • Wear protection during sports

13. Interesting Facts • There are over 100 types of arthritis • Babies start out with 300-350 bones • There are 206 bones in the adult body • Scoliosis is more common in girls than boys

14. Review Questions • What part of the bone produces new blood cells as well as repairing damaged ones? • What are the three types of joins? • What covers and protects our major organs? • What kind of tissue do bones mainly consist of? • How many bones are in an adult body? • Name one way we can maintain the skeletal system.

15. Thank You!