when nerve impulse ease to arrive at neuromuscular junction no more what will b e released into synaptic cleft
the acetylcholine in synaptic cleft will continue to bind to receptors and start impulses unless?
it is removed
the enzyme responsible for breakdown of this neurotransmitter is
if there is no impulse to trigger an opening what happens
pores in sarcoplasmic reticulum will be closed keeping calcium ions from flowing into space around actin and myosin filaments
what will pump any calcium ions remaining in space around actin and myosin filaments back into sarcoplasmic reticulum
troponin tropomyosin complex moves back over actin binding sites which prevents
myosin cross bridges from binding to them
the muscle is now at rest and it will elongate if what?
sufficient force is applied to elongate sacromere
what is the immediate source of energy for muscle contraction
there is only enough ATP for a very shhort period of full contraction for how long?
why is there only enough ATP for a short period?
because the demands of muscle tissue are so high.
the muscle cell fiber will have
15 bill. myosin filaments
each thick filament can breakdown how many ATP molecules per second?
with such high rates of usage, the stores of ATP are used up
a second source of energy is
The ATPase of myosin filaments cannot use what directly?
what can creatine be used for?
to regernate ATP from ADP
what does remaining energy for muscle contraction come from
what provdes energy for 2 minutes of contraction
what provides enough energy for 40minutes?
glycolysis with citric acid cycle
what carries oxygen in blood to muscle fibers
what is found in muscle fibers and can bind to and temporarily store some oxygen within muscle fibers
helps buffer any losss of oxygen rich blood that may occur as muscles contract and temporarily squeeze blood vessels diminishing blood flow
what does smooth muscle of eyes require
nervous or hormonal signal to contract
the more common type of smooth muscle is called
visceral smooth muscle formed by cells closely together
what are visceral smooth muscles linked by
what are wave like contractions
where is visceral smooth muscle found
intestines stomach urninary bladder and uterus
the calcium ions that trigger contractions in cardiac muscle come from
the contractions of cardiac muscle cannot be
contractions of smooth muscle can be
what are cardiac cells connected by
gap junctions that synchornize contraction