Autonomic Nervous System and Muscle Physiology Flashcards
what’s the thin/thick filament ?
thin = actin
thick = myosin
how many steps are there of the neuromuscular junction ?
- AP travels down motor neuron, to presynaptic terminal
- activation and opening of the voltage-gated CA channels
- ACh-containing vesicles fuse with the post-synaptic membrane and release ACh
- binding of neurotransmitter to ligand-gated ion channels on muscle
- ACh brain down by acetylcholinesterase
the more ACh released =
the more that binds
what’s the breakdown of the structure of skeletal muscle ?
- muscle cell/fiber
- myofibrils
- myofilaments
- thick and thing myofilaments
what are muscle fibers made of ?
myofibril
what are muscle fascicle’s ?
When a group of muscle fibers is “bundled” as a unit within the whole muscle
what type of muscle is long and cylindrical in length ?
skeletal muscle cells
are skeletal muscles cells striated or non-strated ?
striated
what is a myofibril ?
organelle composed of bundles of myofilaments
what are sarcomeres ?
contractile unit of myofibril
what does troponin A bind to ?
actin
what does troponin C bind to ?
calcium
what does troponin T bind to ?
tropomyosin
what is troponin ?
protein attached to both actin and tropomyosin that holds tropomyosin over myosin binding site on actin
once myosin binds to actin, what does this form ?
cross bridge
what do myosin heads undergo ?
power stroke
do thin myofilaments change in length ?
no
do thick myofilaments change in length ?
no
do sarcomeres change in length ?
no
what three things happen during a contraction of the sliding filaments theory ?
- binding of myosin to actin forms a cross bridge
- myosin head changes shape and a power stroke occurs
- thin myofilaments slide past thick myofilaments - sarcomere shortens
what is the autonomic nervous system ?
voluntary control of certain movements
wha are the three main divisions of the ANS ?
- sympathetic nervous system
- parasympathetic nervous system
- eneteric nervus system
how is the ANS split ?
left and right side
which division of the ANS is left side/right side ?
left side = SNS
right side = PSNS
what is sympathetic nervous system ?
fight or flight
what is the parasympathetic nervous system ?
rest and digest
what is the primary role of the ANS ?
to maintain homeostasis
what does the ANS help regulate ?
- heart rate
- blood pressure
- body temperature
- gastrointestinal and bladder motility
- gland secretions
- regulates blood glucose levels
- sexual function, etc.
what do sensory afferent fibers do ?
these receptors send signals back to the CNS
what do sensory receptors do ?
monitor internal environment/organs