Chapter 10 – Study Guide


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)



neuromuscular junction (NMJ)


satellite cells


T (transverse) tubules



sarcoplasmic reticulum (SR)

muscular atrophy

muscular hypertrophy


thick filaments

thin filaments

Z discs






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


synaptic cleft


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


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