In which of the following situations is calcium moving through a channel in the pacemaker membrane driven by concentration but against charge? O during the repolarization phase of the action potential, just before the channel closes O during the depolarization phase of the action potential, just after the channel opens O never O at all times that sodium is moving through the membrane O during the repolarization phase of the action potential, just after the channel opens O during the depolarization phase of the action potential, just before the channel closes O during the pacemaker potential, just before the funny channel closes

In which of the following situations is calcium moving through a channel in the pacemaker membrane driven by concentration but against charge? O during the repolarization phase of the action potential, just before the channel closes O during the depolarization phase of the action potential, just after the channel opens O never O at all times that sodium is moving through the membrane O during the repolarization phase of the action potential, just after the channel opens O during the depolarization phase of the action potential, just before the channel closes O during the pacemaker potential, just before the funny channel closes

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter35: The Nervous System

Section: Chapter Questions

Problem 2VCQ: Figure 35.11 Potassium channel blockers, such as amiodarone and procainamide, which are used to...

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The next patient seen by the same doctor was suffering from hyperkalemia and was experiencing cardiac arrhythmias. Which of the following reason/s explain/s why this patient was experiencing cardiac arrhythmias? O hyperkalemia leads to an increase in action potential generation because potassium ions in the ECF makes the resting membrane potential more negative O hyperkalemia leads to a decrease in action potential generation because the potassium ion level in the ICF will cause hyperpolarization O hyperkalemia leads to an increase in action potential generation because the high level of potassium ions in the ICF will make achieving threshold easier O a and b
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The motor end plate is extensively folded to allow for a greater number of what structures? Terminal cisternae Transverse tubules Cholinergic receptors O Myofibrils OParking spaces. Too bad WSU doesn't have motor end plates.
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Figure 35.11 Potassium channel blockers, such as amiodarone and procainamide, which are used to treat abnormal electrical activity in the heart, called cardiac dysrhythmia, impede the movement of K+ through voltage-gated K+ channels. Which part of the action potential would you expect potassium channels to affect?
A significant structural feature in the microscopic studyof cardiac muscle cells is the presence of gap junctionsbetween neighboring cells. Why are these junctions soimportant?