Egta is a substance that binds calcium ions. imagine an experimental setup with a motor neuron and a muscle fiber. stimulation of the motor neuron causes contraction of the muscle fiber through activity at the neuromuscular junction and excitation-contraction coupling. now, inject the muscle fiber with egta. which of the following effects would egta have on excitation-contraction coupling after the neuron releases acetylcholine at the neuromuscular junction?
a) it would prevent conduction of an action potential along the sarcolemma.
b) it would prevent the junctional folds from triggering an action potential.
c) it would prevent the release of calcium ions from the terminal cisterns.
d) it would prevent myosin from forming cross bridges with actin.

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.