Neuro/Hist Stuff Flashcards
tropomyosin
runs in groove made by f actin
binds to troponin complex
troponin T
binds the complex to tropomyosin
troponin I
inhibits the binding of myosin to actin
troponin c
binds Ca (only found in striated muscle)
Type I muscle fibers
contains slow ATPase, red with lotso myoglobin
slow less powerful contractions
contract for long time without fatiguing
Type IIa fibers
largest and most prevalent
intermediate ATPase and provides power
primarily aerobic, intermediate fatigue
Type IIb fibers
fast ATPas, produces fast contractions
mostly anaerobic
rapid fatigue
low mito and low myoglobin
parts of the synapse
presynaptic knob (axon terminal)
synaptic cleft
presynaptic membrane
postsynaptic membrane
synaptic vesicles in presynaptic knob contain
NTMs that released into the synaptic cleft by exocytosis
NTM binds to receptors on the postsynaptic membrane and exmaples of these are
Acetylcholine and noradrenniline
the binding stimulates the postsynaptic cell
every skeletal muscle cell receives an axon terminal but not all
cardiac or smooth muscles cells are direclty innervated
axon terminals are the ends of
nerve fibers that store and release chemical messengers (NTMs) at neuromuscular junctions
synaptic cleft
space between the axon terminal and muscle cell plasma membrane (sarcolemma) `
neuromuscular action
Ach stimualte changes in the sarcolemma that edxcite the muscle fiber
this stimulus is carried down to T tubules to initiate diber contraction
enzymes in the synapic cleft break down the Ach and lmiti its action to a single muscle twitch
golgi tendon organ
encapsulated receptors found within myotendinous junctions that sense tenion within tendons
