2. The Musculoskeletal System 12/24/20151 http://www.youtube.com/watch?v=C2dTbJDQ3u0

3. The Musculoskeletal System The organs of the musculoskeletal system are the bones and skeletal muscle. It supports the body, protects delicate organs, and makes movement possible. 12/24/20152

4. Structural features of the Skeleton There are three types of connective tissue in the skeleton – Bones – Cartilage – Ligaments 12/24/20153

5. Bones Bone tissue is hard and dense. It consists of bone cells within a matrix of minerals and collagen fiber. Canals inside the bones contain nerves and blood vessels. Only a small percentage of bone tissue is actually living. 12/24/20154

6. Bones provide structure & support for body. Some bones protect soft internal organs. Bones store calcium and other minerals needed by body. Some bones contain marrow which produces red and white blood cells. 12/24/20155

7. Ligaments Ligaments hold the bones together at the joints. They are tough but elastic connective tissues. Made of long fibers of collagen. Cartilage Made up of special cells in a matrix of collagen fibers Provides a strong, flexible, low-friction support for bones and other tissues. 12/24/20156

8. 7 About how many muscles do you think the human body has? Answer = 650

9. Where do we have muscles? 12/24/20158 We have muscles all over our body! Face Tongue Eyes Legs Arms Heart Hands Ears Neck Stomach

10. How many muscles do you think are in our face and neck? 12/24/20159 Our face and neck contain about one-fourth of the muscles in our body. That is about 162 muscles.

11. 12/24/201510 Muscles are made of hundreds of tiny fibers that contain specialized protein.

12. What do muscles need? Muscles need oxygen in order to work properly. When they do not get enough oxygen, they can get sore or cramp up. When the muscles in your heart do not get enough oxygen, you can have a heart attack. Can you find a link between musculoskeletal system and other organ systems? 12/24/201511

13. How do muscles move our bones? Do muscles pull or push our bones? 12/24/201512 Muscles pull in order to make our bones move. Our muscles usually work in pairs. One muscle contracts (pulls) while the opposite muscle relaxes

14. When your arm is straight: 12/24/201513 Your bicep is relaxed Your tricep is contracted

15. When your arm is bent: 12/24/201514 Your bicep is contracted Your tricep is relaxed

16. 3 Types of muscles 12/24/201515 There are three different types of muscle in our body. 1.Skeletal muscles 2. Smooth muscles 3. Cardiac muscles

17. Skeletal muscles 12/24/201516 Are voluntary muscles that move bones. Are attached to tendons, which are attached to bones.

18. Cardiac Muscle 12/24/201517 A special kind of involuntary muscle that makes up the heart. The muscles in the heart contract in order to pump the blood through your body. If your muscle stops pumping the blood, you have a heart attack.

19. Smooth Muscles 12/24/201518 Are involuntary muscles that make up the blood vessels, stomach, intestines, and other organs We can not control our smooth muscles Examples: Bladder Uterus Esophagus

20. What happens when we do not use our muscles? 12/24/201519 Our muscles get smaller, which makes them weak. Can you think of some examples of when this may happen?

21. Problems with the Musculoskeletal System Many, such as: Osteoporosis Rheumatoid arthritis Arthritis,… 12/24/201520

22. Homework: Read 3.8 and answer questions 1-6 12/24/201521