Muscular System Flashcards
lecture 1
cardiac muscle
form most of the walls of the heart and adjacent parts of the great vessels
involuntary
branching and anastomosing shorter fibers with transerve striations
skeletal muscle
moves bones and other structures
voluntary
large, long, unbranched, cylindrical fibers with trasverse striations
skeletal muscle classifications
pennate
fusiform
parallel
convergent
circular
pennate: featherlike
(multipennate: deltoid)
fusiform: spindle shaped
(biceps)
parallel: parallel fibers
(obliques)
convergent: broad attachment converge to single tendon
(pectoralis’)
circular: surround a body opening constricting it when contracted
(obiqularis oris/ oculi)
smooth muscle
forms part of the walls of most vessels and hallow organs
involuntary
single, spiral shaped fibers without striations
ANS
basoconstriction/ dilation
contractions of muscles
- origin
- insertion
origin: proximal end, fixed during contraction
insertion: distal end, movable
reflexive contraction
involuntary
muscles of respiration
tonic contractions
slight contraction
muscle tone
maintains posture
electric signals give tone
types of phasic contractions
isometric
isotonic
isometic contractions
no change in length
isotonic contractions
change in length
MOVEMENT
forms of isotonic contractions
concentric
eccentric
concentric contraction
shortening of muscle
deltoid muscle shortens to raise arm into abduction
eccentric contraction
lengthening of muscle
deltoid lengthens allowing gravity to lower arm to adduction
CONTROLS MOVEMENT
