The Skeleton: Support and Movement of the Body

1. Chapter 8 Support and Movement of the Body

2. A. Your Body’s Framework • Skeleton - system of bones that supports and protects the body and the organs inside • The skeleton is also known as the skeletal system. • The skeleton give body it’s shape and protects vital organs like the heart, brain, and lungs. • Muscles attached to bones cause skeleton to move. • 206 bones in skeletal system

3. 6. Two kinds of bones in the head - face bones and bones that protect the brain (form the skull). 7. Middle skeleton consists of ribs and backbone. 8. Backbone made up of vertebrate. 9. There are 12 pairs of ribs (protect heart and lungs) 10. Shoulders made of flat bones - collarbones and shoulder blades. 11. Hips are made of bones shaped like a bowl which helps to support and protect organs

4. 12. Long bones make up arms and legs (filled with soft material called bone marrow) 13. Bone marrow produces new blood cells. 14. Longest , heaviest bone in the body is the femur located in the upper leg 15. When you’re born, your body is mostly cartilage. 16. Cartilage is found in ears, nose, and between vertebrae for padding. {Also found on end of bones for padding.}

5. B. Where Bones Meet • Joint - the place where two or more bones are joined together • Most joints allow bones to move. • Bones are held together at joints by strong cords of tissue called ligaments. • Ball and socket joints - kind of joint that allow the most movement of bones. • Hinge joint - allow bones to move back and forth (knee, fingers, elbow)

6. 6. Skull attached to backbone by pivot joint, which allows side to side movement. 7. Bones of skull cannot move, they have what is called a fixed joint between plates

7. C. Muscles Move Bones • Whole skeletal system is covered with muscles. • Muscles are soft but strong tissue. • Muscles make up muscular system. • You have more than 640 muscles. • Muscles are attached to bone by tough cords called tendons. • To move muscles, contract making them shorter and thicker.

8. 7. When relaxed, muscles are longer and thinner. 8. Most muscles that move bone work in pairs - one pulls in one direction, another pulls in the opposite direction. 9. When one contracts and shortens, the other relaxes and lengthens.

9. D. Two Groups of Muscles • You can control some muscles like the ones that help you walk, run, jump, etc. • These muscles you control are called voluntary muscles. • These muscles are attached to bones and contract and relax. • Some muscles you don’t control. Such as the ones that move food through the intestines or your heart beating.

10. 5. These muscles are called involuntary muscles. 6. There are 3 kinds of muscles: skeletal, smooth, heart 7. Skeletal - muscles made up of long fibers that move bones (voluntary muscles) 8. Smooth- most body organs made of smooth muscle, make up organs, blood vessels, stomach, intestines (involuntary muscles) 9. Heart - special involuntary muscle - hardest working muscle in body (2 - 3 billion beats during a lifetime.

11. E. Bone and Muscle Injuries • A crack or break in a bone is called a fracture. • Simple fracture - bone breaks but doesn’t push through muscle or skin. • Compound fracture - bone breaks and broken end pushes through muscle and skin • Bones contain living tissue so they can repair themselves.

12. 5. Sprain - injury in which a ligament is stretched or torn. 6. Muscle strain - injury caused by overstretching a muscle or tendon. 7. Cramp - sudden strong contraction of a muscle causing pain.

13. F. Care of Bones and Muscle • Three important things a day to keep bones and muscles healthy: • Proper diet • Enough rest • Enough rest