2. Skeletal Skeletal – striated, multinucleate, voluntary, Smooth Smooth - found in walls of hollow visceral organs; ex. stomach, bladder, respiratory passages; visceral, nonstriated, involuntary; discuss peristalsis Cardiac Cardiac – in heart only, striated, involuntary, intercalcated disks

3. Muscle function: produce movement maintain posture stabilize joints generate heat

4. Functional Characteristics: Excitability- respond to a stimulus Contractility- ability to shorten forcibly when adequately stimulated Extensibility- the ability to be stretched Elasticity- the ability of a muscle fiber to resume its resting length after being stretched

5. Skeletal Muscle Tissue

6. Smooth Muscle Tissue

7. Cardiac Muscle Tissue

8. Gross Anatomy Skeletal Muscle

9. bundle of muscle fibers muscle fiber (cell) myofibril sarcomere Muscle Anatomy

10. Muscle Fiber

11. Myofibril

12. Sarcomere Z lines

13. Sarcomere A band

14. Sarcomere I bands

15. Sarcomere H zone

16. Actin and Myosin Filaments myosin actin

17. Myosin (Thick) Filament

18. Actin (Thin) Filament

19. Sliding Filament Hypothesis A Z Z H I I A I I Z Z H Z Z H A I I

20. Actin & Myosin Interaction

21. Biology 100 Human Biology Motor Unit spinal cord motor neurons muscle bundle muscle fibers neuromuscular junctions

22. Neuromuscular junctions branching axon to motor unit muscle fibers

23. axon plasma membrane myofibrils sarcomere

24. T tubules sarcoplasmic reticulum http://www.blackwellpublishing.com/matthews/myosin.html

25. Stimulation of Skeletal Muscle