1. Notes- The Skeletal System

2. Functions I. 5 functions of the skeletal system
A. Gives shape and support to your body.
B. Bones protect internal organs
1. The rib cage, sternum, and vertebrae protect the heart and lungs.
2. The cranium protects the brain.
C. Major muscles attached to bones.

3. Functions D. Blood cells are formed in the red marrow of some bones.
E. Major amounts of calcium and phosphorus are stored. These elements make bones hard.
Notice the red marrow and the compact bone

4. Parts of bones II. Parts of bones 206- 214 bones in your body.
Classified by their shape.
(long, flat and short)

5. Parts of bones C. Parts Periosteum a. Tough, tight – fitting
on the outside of the bone.
b. Small blood vessels carry nutrients into bone.
c. Also important in growth and repair of bone

6. Parts of bones 2. Compact bone
Contains bone cells, blood vessels, calcium, phosphorus, elastic fibers
Elastic fibers keep bones from being too rigid, brittle, or easily broken

7. Disorders c. Rickets and Osteoporosis
are two disorders caused by lack of minerals
Osteoporosis
www. Ihealth

8. Parts of bones 3. Spongy bone Found towards the end of long bones
Has lots of open spaces which cause bone to be light weight.

9. 4. Marrow Cavity
In center of long bones
Filled with fatty tissue called marrow
Produces 2-3 million red blood cells per second
Produces white blood cells also

10. Parts of bones 5. Cartilage Thick , smooth layer over bone’s ends
No blood vessels or minerals
Flexible, absorbs shock, makes movement easier

11. Bone Development III. Bone Development
Before birth, our skeleton is cartilage

12. Bone Development
B. Osteoblast (bone- forming cells) replace cartilage.
C. Osteoclast break down bone and release calcium and phosphorus into your bloodstream.
The blue arrows indicate the osteoblasts. The yellow arrows indicate the bone matrix they’ve just secreted.

14. Fractures
IV. Fractures
A. Break in a bone

15. Fractures B. Types of fractures
Simple : The bone has broken but the ends do not break through the skin.
Compound: Broken ends of bone stick out through the skin.

16. Name the Fracture
It’s kind of tough to tell, but this is a _ _ _ _ _ _ fracture.
What kind of fracture is this?

17. Joints V. Joints Place where two or more bone meet.
Ligaments- tough band of tissue that holds bones together at joints
Types of joints
Immovable
Allows little or no movement
Examples: pelvis and skull
Movable
a. Allows body to make a wide range of movements

18. Joints b. Types Pivot – head and arm (elbow)
Ball and socket- hip and shoulder
Hinge- knee, arm and fingers (conyloid)
Gliding- wrist, ankle and vetebrae
Immovable / Fixed joint – skull (cranium)
Static. How stuffworks.com

19. Hinge joint and pivot joint

20. Know the parts of a skeleton
Posterior View
Frontal View