1. Skeletal System
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2. Skeletal System has five functions.
Function #1: Provides shape and support.
Function #2: Anchor for all of the body’s movement.
Function #3: Protects soft organs inside the body.
Function #4: Makes red blood cells.
Function #5: Stores minerals such as calcium and phosphorus.

3. Organs of the Skeletal System
206 bones (organs) in an adult skeleton

4. Bones are classified by shape:
Long Bones are found in the arms, legs, fingers and toes.

5. Bones are classified by shape.
Short bones are found in wrists, ankles, and knee caps.

6. Bones are classified by shape:
Irregular bones are found in the spine (vertebrae), sacrum, and jaw.

7. Bones are classified by shape:
Flat bones are found in the ribs and skull.

8. The Skeleton is the body’s framework
Axial Skeleton:
Main functions: Provides support and protection
Irregular and flat bones - Skull, ribs, vertebrae, pelvis
Appendicular Skeleton:
Main Functions: to allow movement
Long and short bones: Found in Arms, shoulders, legs– scapula, humerus, radius, ulna, femur, tibia, and fibula

9. There are two types of bone tissue.
Compact bone:
Covers outside of most bones
Very hard and tough
surrounds spongy inner layer.
Basic supportive layer
Spongy bone:
Inside of bone
Strong but lightweight
Makes up most of the short and irregular bones
Makes up the ends of long bones

10. Marrow and Blood Cells Marrow fills spaces within spongy bone.
Marrow produces red and white blood cells.
New blood cells travel from the marrow into blood vessels that run throughout the bone.

11. Joints
Places where two parts (bones) of the skeletal system meet

12. Immovable or Fixed Joints
Lock bones together like puzzle pieces.
Found in skull and pelvis

13. Slightly Movable Joints
Able to flex slightly
Found where ribs connect to sternum (breast bone)

14. Freely Movable Joints Allow your body to bend and move
Found in arms and legs, hands and feet, spine

15. Ligaments Tissues that hold bones together at movable joints
Other structures (cartilage and fat) cushion bones and keep them from rubbing together.

16. Muscular System
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17. 3 Functions of the Muscular System: Movement
Movement: Works with the skeletal system
Skeletal Muscles work in pairs. A muscle on one side of the body pulls in one direction while the other muscle relaxes.
TENDONS attach muscles to bones (stretchy connective tissue)

18. 3 Functions of the Muscular System
Maintaining body temperature – related to homeostasis
When muscles contract, they produce heat
Example: quick muscle contractions when you shiver release heat and raise your body temperature

19. 3 Functions of the Muscular System
Maintaining posture
Most muscles in your body are always a little bit contracted – muscle tone
Muscles that maintain posture only relax when you are unconscious.

20. Your body has different types of muscles.
Each type contracts and relaxes
All have different functions
All are found in different locations

21. Skeletal Muscle Attached to your skeleton
Performs voluntary movement – movement you choose to make
Made of long fibers made up of smaller bundles

22. Skeletal muscles and tendons allow bones to move
Tendons – strong connective tissues that attach skeletal muscles to bones
Tendons are found on each end of a muscle.

23. Skeletal muscles and tendons allow bones to move
Muscle fibers contract, pull on the tendon, which then pulls on the bone to make it move

24. Smooth Muscle
Found inside some organs – example: intestines and stomach
Performs involuntary movement – move without you knowing it
Fibers are not as long as skeletal muscles
Contracts slowly

25. Cardiac Muscle Only found in your heart
Involuntary muscle like smooth muscle – moves without conscious thought
Contracts slowly like smooth muscle

26. Muscles grow and heal. Skeletal muscles have to develop and strengthen
Example: A baby can’t lift its head because neck muscles are not strong enough

27. Muscles grow and heal.
Muscles get bigger when you exercise regularly

28. Muscles grow and heal.
Muscle soreness you feel a day or two after exercise is caused by damage to muscle fibers.