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 cardio ? -please explain  

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If you reduced the outward current in a heart cell, what would be the result?

A. Increase the rate of repolarization.
B. Prolong the action potential.
C. Increase the rate of depolarization.

...... i thought the answer was c but is b... can someone explain. the outward current is established by the flow of potassium outside of the cell. right? so if potassium doesn't flow out wouldn't it make the cell more positive and increase the rate of depolrization?


it will prolong the action potential of the heart cell by blocking the potasssium channels, prolong the phase 1 and 3 of the action potential actually, due to the prolong of the refractory phase, it will decrease the heart rate and decrease the depolization rate of the heart.
you may correlate this with anti-arrythemic drugs and will realize it.


yes it should be B


okay... i understand now. :P

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