1. skeletal muscle
    invervated by axons of motor neurons belonging to the somatic division of the nervous system
  2. motor unit
    muscle fibers innervated by a single motor neuron contract stimultaneously
  3. myofibers, muscle fibers
    cylinder-shaped cells
  4. myofibrils
    smaller bundles of contractile filaments
  5. myofilaments
    contractile filaments
  6. endomysium
    connective tissue sheath
  7. fascicles
    sheathed fibrs are grouped together in bundles
  8. perimysium
    connective tissue
  9. epimysium
    dense fibrous connective tissue
  10. deep fascia
    sheet of fibrous connective tissue
  11. smooth (or visceral) muscle are not
    • striated, less in cylindrical shape compared with skeletal muscle fibers
    • have a single nucleus (found in center of the fiber)
  12. cardiac muscle
    • found only in the heart, similar to skeletal muscle (striated)
    • exhibits rhythmicity and spontaneity
    • junctions between cardiac muscle fibers (called intercalated discs)
  13. ligament
    fibrous tissue binding bones together or lashing tendons or muscles in place
  14. muscle
    contractile organ capable of producing movement
  15. belly
    fleshy part of a muscle
  16. head
    portion of a muscle having a seperate origin
  17. tendon
    fibrous tissue securing a muscle to its attachment
  18. aponeurosis
    expanded tendon for attachment of a flat muscle
  19. fascia
    fibrous envelopment of muscular structures
  20. sheath
    protective covering
  21. origin
    relatively fixed point of muscle attachment
  22. insertion
    relatively moveable point of a muscle attachment
  23. action
    movement accomplished by a muscle
  24. flexion
    to decrease the angle between two bones
  25. extension
    increase angle between two bones
  26. hyperextension
    increae angle between two bones past the plane of the anatomical position
  27. elevation
    to raise
  28. depression
    to lower
  29. abduction
    to draw away from midline
  30. adduction
    draw toward the midline
  31. erection
    draw upright
  32. tension
    to draw tight
  33. rotation
    cause to revolve, internal rotation, external rotation
  34. supination
    to turn palm of hand upward
  35. pronation
    turn palm of hand downward
  36. corrugation
    to draw (skin) into wrinkles
  37. sphincter
    regulates the closing of an aperture
  38. eversion
    to cause to point outward away from the midline
  39. inversion
    to cause to point inward toward midline
  40. retraction
    to pull shoulders back
  41. protraction
    to pull shoulders forward
  42. innervation
    pattern of distribution of nerve fibers in a tissue or organ
  43. somatic nervous system
    division of NS which innervates skeletal muscle
  44. autonomic nervous system
    division of NS which innervates smooth muscle, heart and glands
  45. tetanus
    brief, sustained contraction resulting from high frequency stimulation
  46. contracture
    progressive failure of muscle to regain its original length following prolonged stimulation
  47. myogenic
    originating within muscle
  48. refractory period
    period of time following stimulation when a second stimulus does not produce a result
  49. neurotransmitters
    chemical, released at nerve ending responsible for producing the effects of nerve stimulation
  50. muscle twitch
    response of muscle to a single, brief threshold stimulus
  51. threshold stimulus
    stimulus strength at which muscle contraction occurs
  52. motor unit summation
    multiple motor units invovled in contraction, producing a smooth continuous response
  53. recruitment
    involves the number of motor units invovled in contraction
  54. temporal summation
    occurs when stimuli are delivered so frequently that muscle does not completely relax after first stimulus and second contraction is stronger than first
  55. isotonic contraction
    muscle changes in length, but remains constant during contractile period
  56. isometric contraction
    tension increases, but muscle does not change in length
Card Set
Anatomy and Physiology