1. The Skeletal System 6 th Grade

2. Are bones in your body alive? What are they made of? YES! The bones in your body are alive – Made of tissues that have cells that take in nutrients and use energy

3. Skeletal System is the FRAMEWORK of your body: What its 5 major functions?

4. Reason #1: Gives SHAPE and SUPPORT to your body

5. Reason #2: PROTECT your internal organs – Ex. skull protects your brain – Ex. ribs surround the heart and lungs

6. Reason #3: Muscles are attached to the bone and help bones move

7. Reason #4: Blood cells are formed in the center of many bones in soft tissue called RED MARROW

8. Reason #5: Large quantities of CALCIUM and PHOSPHORUS are stored in the skeleton for later use  these make bones hard

9. Are bones smooth or rough? Rough: have bumps, edges, round ends, rough spots, many pits and holes

10. Periosteum A living bone’s surface covered with a tight- fitting membrane

11. Under the periosteum, what are the 2 types of bone tissue? Compact Bone Tissue: Spongy Bone Tissue:

12. Compact Bone Tissue – HARD structure that gives bones strength – Contains deposits of calcium and phosphorus – Bone cells and blood vessels are found in this layer --keeps the bone from being too rigid, brittle or easy to break --even though it is hard, it is still ALIVE

13. Spongy Bone Tissue Located at the end of long bones Has many small open spaces to make your bones lightweight

14. What is in the center of long bones? Large openings called CAVITIES

15. The cavities and spaces in spongy bone are filled with MARROW

16. Red vs. Yellow Bone Marrow

17. What is cartilage?

18. What is Cartilage? A smooth, slippery, thick layer of tissue that covers the ends of bones Flexible, important to joints because it reduces friction so that bones to not rub together People with damaged cartilage have pain when they move

19. Cartilage

21. How many bones does an adult have? 206

22. Bone Cells Osteoblasts: build up bone by depositing calcium and phosphorus to make them strong Osteoclasts: break bone down, releasing calcium and phosphorus into the bloodstream – Your body needs these elements to move your muscles

23. What are joints? What are ligaments? Joints: Any place where 2 or more bones come together they do not rub against each other Ligaments: a tough band of tissue that hold joints in place

25. Ligaments vs. Tendons Ligaments connect BONE to BONE Tendons connect BONE to MUSCLE https://www.youtube.com/watch?v=PdJ5QDkq G2g