1. MUSCULAR SYSTEM pp

2. FUNCTION
Support, movement, and protection

3. Types of Muscle

4. Types Skeletal Muscle Voluntary Muscle that moves bones
Over 400 skeletal muscles
Long cells with several nuclei along edge
Stripes called striations visible under high power

5. TYPES 2. Smooth Muscle Involuntary muscles that protect organs
Movement of intestines, esophagus, stomach, and other organs

6. TYPES 2. Smooth Muscle Contract slowly and smoothly
Usually one nucleus per cell in middle
No striations

7. TYPES 3. Cardiac Muscle Involuntary muscles
Contract heart and certain blood vessels

8. TYPES 3. Cardiac Muscle Strongest type of muscle
Only one nucleus per cell
Branching Cells
Some striations (not as much as skeletal)

9. MUSCLE STRUCTURE
myofibril muscle cell (fiber)fascicle muscle

11. Muscle Structure
Two types of proteins (actin and myosin) involved

12. Muscle Structure actin filaments anchored to Z line
Sarcomere: functional unit from Z line to Z line

13. MUSCLE CONTRACTION
contraction: shortening of sarcomere between Z – lines

14. MUSCLE CONTRACTION
Myosin “heads” walk along the actin (shortens sarcomere)
Movement of myosin requires ATP

15. MUSCLE FATIGUE
The inability to contract the muscle due to the lack of ATP

16. Body Reacts by… Increasing breathing Increasing heart rate
Increasing production of ATP by breaking down fats