skeletal
muscle tissue - usually attached to bones - striated - under voluntary control
cardiac
muscle - makes up most of wall of heart - striated - under involuntary control
smooth
muscle - located in walls of various structures - nonstriated - under
involuntary control
muscle
cell = muscle fiber
superficial
fascia
deep
fascia (won’t ask about epimysium, perimysium, endomysium)
tendon
aponeurosis
neuromuscular
junction (NMJ)
myoblasts
satellite
cells
sarcolemma
T
(transverse) tubules
glycogen
myoglobin
sarcoplasmic
reticulum (SR)
muscular
atrophy
muscular
hypertrophy
myofibrils
thick
filaments
thin
filaments
Z
discs
sarcomere
myosin
actin
tropomyosin
troponin
excitation
– contraction events (know events & relative sequence of events)
muscle action potential travels
along sarcolemma and through T tubules
sarcoplasmic reticulum (SR)
releases calcium ions
released calcium ions combine
with troponin
troponin-tropomyosin complex
changes shape uncovering myosin binding sites on actin
myosin head hydrolyzes ATP and
becomes reoriented & energized
myosin head binds to actin
myosin head moves causing thin
and thick filaments to slide past eachother
myosin head binds ATP and
detaches from actin
length
tension relationship – forcefulness of muscle contraction depends on sarcomere
length before contraction begins
synapse
synaptic
cleft
neurotransmitter
synaptic
end bulbs
synaptic
vesicles
acetylcholine
(ACh)
motor
end plate
acetylcholine
receptors
3
sources for ATP production in muscle fibers
creatine phosphate (1 ATP /
creatine phosphate)
anaerobic cellular respiration
(2 ATP / glucose)
aerobic cellular respiration (36
ATP / glucose)
motor
unit
small
motor units used for precise movements
large
motor units used for large scale powerful movements
myogram
twitch
contraction
refractory
period
wave
summation
unfused
tetanus
fused
tetanus
motor
unit recruitment
muscle
tone
isotonic
contractions
isometric
contractions
slow
oxidative (SO) fibers
fast
glycolytic (FG) fibers
fast
oxidative-glycolytic (FOG) fibers
intercalated
discs
cardiac
muscle remains contracted 10-15x longer than skeletal muscle in response to a
single action potential
visceral
(single-unit) smooth muscle tissue
multi-unit
smooth muscle
intermediate
filaments attached to dense bodies
smooth
muscle contractions start more slowly and last much longer than skeletal muscle
contractions
smooth
muscle can stretch considerably and still maintain contractile function
growth
of skeletal muscles after birth is due to hypertrophy NOT hyperplasia
limited
muscle damage can be repaired by satellite cells
extensive
muscle damage is repaired by fibrosis