1. Muscular System

2. Vocabulary bi- two -ia condition of -lysis destruction, dissolve myo- muscle -plegia paralysis tri- three tendo- tendon para- lower half fasci- fibrous band Carp – wrist

3. ad- to, toward or near ab- from, away circum- around inter- between, among

4. General Info Consists of 650 muscles Muscles are bundles muscle fibers held together by connective tissue

5. Properties Excitability –Ability to respond to a stimulus such as a nerve impulse Extensibility –Ability to be stretched Elasticity –Allows the muscle to return to its original shape after it has contracted or stretched

6. ●Contractibility -Muscle fibers stimulated by nerves contract or become shorter and thicker which causes movement

7. Types of Muscles Skeletal –Attached to bones and causes movement

8. Cardiac Muscle Found only in the heart Contracts to circulate blood

9. Visceral Muscle Also called smooth Found in all internal organs

10. Functions of Muscles Attaches to bones to provide voluntary movement Produces heat and energy Helps maintain posture Protects internal organs

11. Tendons Strong, tough, connective tissue One way skeletal muscles attach to bones Ex: Achilles →

12. Fascia Tough sheet-like membrane that covers and protects tissue Ex: back

13. Muscle Actions Origin –End of the muscle that does not move Insertion –End of the muscle that does move

14. Muscle Movements Adduction –Moving a body part toward the midline

15. Abduction Moving a body part away from the midline

16. Flexion Decreasing the angle between 2 bones or bending a body part

17. Extension Increasing the angle between 2 bones or straightening a body part

18. Rotation Turning a body part around it’s own axis

19. Circumduction Moving in a circle at a joint while the other end stays stationary

20. Muscle Tone State of partial contraction Muscles have some tone at all times

21. Atrophy Lack of muscle tone Occurs when muscles are not used for a long period of time they shrink in size and lose strength

22. Contracture A severe tightening of a flexor muscle resulting in a bending of a joint Ex: Foot drop

25. Diseases Muscular Dystrophy –Group of inherited diseases that lead to chronic progressive muscle atrophy Fibromyalgia –Widespread pain in specific muscle sites –S/S muscle stiffness, numbness, tingling, pain Muscle Spasms –Cramps –Sudden involuntary muscle contraction Strain –Overstretching of or injury to a muscle or tendon