1. Muscular System Your muscular system moves all your moving parts… 600 Muscles

2. What does the muscular system do? Accounts for all of the ways that the parts of the body moves Running, eating, breathing, digesting, and pumping blood Also, helps protect your joints and helps create the heat that keeps your body warm

3. What are muscles made of? Bundles of special cells called muscle fibers make up muscles Muscle fibers are made of long, paired strands of proteins Muscles can contract because of the way the paired strands are linked Like a ladder

4. Who or what tells the muscles to move? Who is the boss? Who is the boss? Skeletal muscles must be stimulated by a nerve to contract Skeletal muscles must be stimulated by a nerve to contract Motor unit Motor unit One neuron One neuron Muscle cells stimulated by that neuron Muscle cells stimulated by that neuron

5. The whole story of a muscle contraction… http://www.youtube. com/watch?feature= player_detailpage&v =kvMFdNw35L0 This is a little more detailed than what we will review in class but you will need to know the basic idea of contraction.

6. Are all muscles the same? Three basic muscle types are found in the body Three basic muscle types are found in the body Skeletal muscle Skeletal muscle Cardiac muscle Cardiac muscle Smooth muscle Smooth muscle

7. Skeletal Muscle Or, striated (striped) muscle See human nerve smear below This is the type of muscle that causes you to move voluntarily

8. Skeletal Muscle Attachments- needs to connect somewhere so the skeletal system will move Sites of muscle attachment Sites of muscle attachment Bones Bones Cartilages Cartilages Connective tissue coverings Connective tissue coverings Example of connective tissue Example of connective tissue Endomysium (end-uh-myz-e-am) Endomysium (end-uh-myz-e-am) The connective tissue layer surrounding an individual skeletal muscle fiber. The connective tissue layer surrounding an individual skeletal muscle fiber. Perimysium (per-uh-myz-e-am) Perimysium (per-uh-myz-e-am) The sheath of connective tissue enveloping bundles of muscle fibers. The sheath of connective tissue enveloping bundles of muscle fibers. Epimysium (epa-myz-e-am) Epimysium (epa-myz-e-am) The external sheath of connective tissue surrounding a muscle. The external sheath of connective tissue surrounding a muscle.

9. Smooth Muscle Cause involuntary movements of the eyelids, internal organs, and blood vessels Has no striations Has no striations Involuntary – no conscious control Involuntary – no conscious control Found mainly in the walls of hollow organs Found mainly in the walls of hollow organs

10. Cardiac Muscle Characteristics Special kind of involuntary, striated muscle found only in the walls of the heart slide of cardiac muscle tissue

11. How do we move? Skeletal system works with muscular system Movement is attained due to a muscle moving an attached bone Movement is attained due to a muscle moving an attached bone

12. Five Golden Rules of Gross Muscle Activity 1. all muscles cross at least one joint 2. bulk of muscles lies proximal (nearest) to the joint crossed 3. all muscles have at least 2 attachments: origin & insertion 4. muscles only pull/never push 1. Either pull the joint into a bent position or pull it straight 2. Muscles usually work in pairs, one on either side of the joint 3. When one contracts, the other relaxes 5. during contraction the muscle insertion moves toward the origin

13. Lifting a pencil verse a couch… Muscle force depends upon the number of fibers stimulated Muscle force depends upon the number of fibers stimulated More fibers contracting results in greater muscle tension More fibers contracting results in greater muscle tension Muscles can continue to contract unless they run out of energy Muscles can continue to contract unless they run out of energy

14. Why do muscles get tired? Muscles need oxygen in order to produce the energy needed for contracting Muscles working very hard use up all the oxygen at hand When this happens, less energy is available for creating contractions, which makes you feel weak or tired

15. What happens if you can’t get tired? (Odd question) If you are running from a tiger, you can’t quit just because your muscles ran out of oxygen… in order for muscles to keep working without oxygen, a process that makes the chemical lactic acid provides a small amount of energy Unfortunately, lactic acid is poisonous to cells Muscles need extra oxygen to get rid of lactic acid before they can make more energy Extra oxygen needed to rid the body of lactic acid is called an oxygen debt Only time and rest can erase an oxygen debt

16. Effects of Exercise on Muscle Aerobics result in stronger muscles due to increase blood supply Aerobics result in stronger muscles due to increase blood supply Muscle fibers increase oxygen storage Muscle fibers increase oxygen storage Muscle becomes more fatigue resistant Heart enlarges to pump more blood to body Heart enlarges to pump more blood to body Does not increase skeletal muscle size Does not increase skeletal muscle size

17. Effects of Exercise on Muscle Results of increased muscle use from resistance training Results of increased muscle use from resistance training Individual muscle cells make more contractile filaments & connective tissue increases Individual muscle cells make more contractile filaments & connective tissue increases Increase in muscle size Increase in muscle size Increase in muscle strength Increase in muscle strength

18. Aging Connective Tissue increases Connective Tissue increases Amount of Muscle tissue decreases Amount of Muscle tissue decreases Muscles become stringier(sinewy) Muscles become stringier(sinewy) Body weight declines due to loss of muscle mass Body weight declines due to loss of muscle mass By age 80, muscle strength usually decrease by 50% without weight training exercises By age 80, muscle strength usually decrease by 50% without weight training exercises

19. Names of Muscles The next 8 slides show the location and names of the major muscles.

20. Where are the major muscles? (First 2 minutes 45 seconds of video) http://www.youtube.com/watch?v=7Ox -NOJMhKo&feature=related

21. Head and Neck Muscles

22. Trunk Muscles

23. Deep Trunk and Arm Muscles

24. Muscles of the Pelvis, Hip, and Thigh

25. Muscles of the Lower Leg

26. Superficial Muscles: Anterior

27. Superficial Muscles: Posterior