You are studying a disease in which muscle becomes weak due to difficulty in generating action potentials.
Shown on the left are the responses of a control muscle fiber and a diseased muscle fiber to various levels of depolarizing ( positive ) current injection.
On the right are shown the responses of the same two fibers to a 10 nA ( 10-9A ) injection of hyperpolarizing ( negative ) current.
https://docs.google.com/spreadsheets/d/1BXYugUqxdMbJOzF7KYZInowUu9bOUavi2shYJFBz6p4/edit?usp=sharing
Determine the resting membrane potential of each fiber. Also graph the current versus voltage plot for each fiber
Control RMP =
Disease RMP =
Calculate the input resistance of each fiber.
Let Control
Let Disease
Then from the graphs , the slope is the same thing as conductance
conductance = opposite of resistance
Measure the time constant of each fiber.
Given the difference in resting potential and the response to hyperpolarizing ( negative ) current injection , predict what functional change might account for the reduced excitability of the disease cell.
the disease state has an increased amount of potassium conductance at the resting state
it has a shorter time constant , so it charges and discharges the membrane faster
they probably have upregulated potassium channels somehow