1. Muscle Physiology

2. Functions of Muscular Tissue Producing Body Movements Stabilizing Joints Maintaining Posture Producing heat Properties of Muscular Tissue Excitability Contractility Extensibility Elasticity

3. Types of Muscle

5. Connective Tissue Wrappings

6. Insertion - attachment to a movable bone Origin - attachment to stationary bone Attachment - connective tissue layers extend to attach to bone (tendon or aponeurosis) Muscle Attachments

7. Anatomy of a Muscle Fiber

10. Sarcomere Dark(A) & light(I) bands visible with an electron microscope

11. Sarcomere

12. Thick and Thin Filaments

13. Sliding Filament Mechanism Relaxed Muscle Contracte d Muscle

14. The Contraction Cycle

15. Stimulation and Contraction

16. Neuromuscular Junction

17. Summary

18. Motor Unit: A motor neuron and all the muscle fibers it innervates. Motor Unit

19. Muscle Tone Involuntary contraction of a small number of motor units which leads to partial state of contraction of relaxed muscles Keeps muscles firm even though relaxed Essential for maintaining posture

20. Contraction of a Skeletal Muscle Muscle Twitch: Response of a muscle to a single stimulus

21. Graded Muscle Responses 1. Frequency of stimulation Wave summation and Tetanus 2. Strength of the stimulus Motor Unit Recruitment Graded - variation in degree of contraction Contraction of a Skeletal Muscle More motor units stimulated which leads to more muscle fibers responding.

22. Wave Summation and Tetanus

23. Isotonic and Isometric Contractions Isotonic - muscle changes length load is moved Isometric - muscle applies tension but does not move the load

24. Muscle Metabolism

25. Types of Skeletal Muscle Fibers

26. Muscle Fatigue Inability to contract after prolonged activity –central fatigue is feeling of tiredness and a desire to stop (protective mechanism) –depletion of creatine phosphate –decline of Ca 2+ within the sarcoplasm Factors that contribute to muscle fatigue –insufficient oxygen or glycogen –buildup of lactic acid and ADP –insufficient release of acetylcholine from motor neurons