During extreme dehydration, plasma K* can increase to as high as 10 mM. (A) What would the membrane potential of this neuron be under these conditions? (Assume there are no other changes in ion concentrations.) (B) What would happen to the ability of the neuron in the preceding question to generate action potentials during extreme dehydration? Why might this be problematic? HINTS: You can assume that PK is 100 times the other Ps. Look up average AP threshold, in textbook or use value from next question to answer part B. Be careful how to handle [CI] because of its negative charge.

During extreme dehydration, plasma K* can increase to as high as 10 mM. (A) What would the membrane potential of this neuron be under these conditions? (Assume there are no other changes in ion concentrations.) (B) What would happen to the ability of the neuron in the preceding question to generate action potentials during extreme dehydration? Why might this be problematic? HINTS: You can assume that PK is 100 times the other Ps. Look up average AP threshold, in textbook or use value from next question to answer part B. Be careful how to handle [CI] because of its negative charge.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 4TAHL: Assume presynaptic excitatory neuron A terminates on a postsynaptic cell near the axon hillock and...

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