1. Muscle Physiology
Distinguish between the 3 types of muscles and describe the four main functions of muscles

3. Functions of Muscles
Producing Movement- such as quick movements, expressing emotion, circulating blood.
Maintaining Posture- Mainly through skeletal muscles which make tiny adjustments continuously.
Stabilizing Joints- through muscle tendons
Generating Heat- skeletal muscle accounts for 40% of body mass and most responsible for heat generation through muscle contractions

4. Skeletal Muscles
Location: attached to bones or to skin (mainly facial muscles)
Shape and appearance: single, very long, cylindrical, multinucleated cells with obvious striations.

5. Skeletal Muscle: Can you see the striations and multiple nuclei???

6. Skeletal Muscle continued……
Connective Tissue: Epimysium, perimysium, and endomysium
Regulation of contraction: Voluntary, via nervous system control

7. Skeletal Continued….
Regulation of contraction: Voluntary via nervous system controls
Speed of contraction: Slow to fast
Rhythmic Contraction: NO
Remember: Skeletal, Striated, and Voluntary

8. Cardiac Muscles Body Location: Walls of the heart
Cell shape and appearance:
Branching chains of cells; uninucleate, striations; intercalated discs

11. Cardiac Muscle Continued…
Connective Tissue Components: Endomysium attached to the fibrous skeleton of the heart.
Regulation of contraction: Involuntary; the heart has a pacemaker (keeps the rhythm); also nervous system controls; hormones

12. Cardiac Muscle Continued…
Speed of contraction: Slow
Rhythmic Contraction: Yes
Remember: Cardiac, striated, and involuntary

13. Smooth Muscle
Body Location: Mostly in walls of hollow visceral organs (other then the heart)
Cell shape and appearance: Single, fusiform, uninucleate; no striations

15. Smooth Muscle Continued
Connective Tissue Components: Endomysium
Regulation of Contraction: Involuntary; nervous system controls; hormones; chemicals; stretch

16. Smooth Muscle Continued….
Speed of Contraction: Very Slow
If skeletal muscle was a speedy car then smooth muscle would be a heavy-duty construction vehicles (CAT)
Rhythmic Contraction: Yes, in some

17. Review
How do cells of the 3 types of muscle tissue differ from one another anatomically?
Which muscle type has the most elaborate connective tissue wrappings?
What does striated mean relative to muscle cells?
How do movements promoted by skeletal muscles differ from those of smooth muscle?