1. Skeletal System

2. Organization of Living things
Cells
Tissues
Organs
Organ Systems
Organism

3. What is a skeleton? A SKELETON is a framework.
The adult human body is made up of 206 bones
Babies have about 350 bones.

4. functions of the skeletal system:
Provides shape
Provides support
Allows for movement
Protects vital organs
Produces and stores needed substances like blood (makes) and calcium (stores)

5. Parts of the skeletal system joints:
Joint – allows bones to move in different ways.
Ligaments – connective tissue that connects bone to bone.
Cartilage – connective FLEXIBLE tissue that covers the ends of bones and acts as a cushion.
Knee Joint

6. 2 categories of joints:
Immovable Joints – allows little or no movement (ex: bones in the skull)
Movable joints – allow movement
4 types:
Hinge Joint - forward and backward movement (ex: knee, fingers, toes)
Ball and Socket Joint – allows circular movement and the greatest range of motion (ex: shoulder, hip)
Pivot joint – allows one bone to rotate around another (Elbow)
4. Sliding joint-allows one bone to slide over another (ex: wrist and ankles)

8. Bones…..the Organ:
Bones are organs made up of many different types of tissues.
Long Bone Anatomy: 4 layers
Periosteum – outer layer of the bone, contains blood vessels and nerves
Compact Bone – next to periosteum, hard and dense
Spongy Bone – has many small spaces that help to make bones lightweight
Marrow – soft connective tissue found on the inside of bones
Red Marrow: produces some of the body’s blood cells
Yellow Marrow: stores fat that can serve as an energy reserve

9. Continued:
Bone Strength – bone structure makes them both strong and lightweight. Bones are stronger than concrete or granite rock!!
Bone Growth – bones continue to “grow” make new bone tissue.

10. Bone health
A combination of a balanced diet and regular exercise are important for a lifetime of healthy bones.
Healthy Diet – important nutrients (calcium and phosphorus)

11. EXERCISE
Weight bearing activities help bones grow stronger and more dense (ex: running, lifting weights, skating, dancing)

12. Skeletal system disease and injuries:
Diseases:
Osteoporosis – bodies bones become weak and break easily. More common in older women. Prevention begins early.

13. Continued:
Arthritis – a disease of the joints in which cartilage breaks down.