Question

Please select the best option for each part.

Part A. The absolute refractory period of the action potential____________. (assume Temp = 37 degrees Celcius)

a. determines the maximum frequency at which action potentials can be generated

b. occurs because voltage-gated K+ channels have not recovered from inactivation

c. does not occur in skeletal muscles

d. occurs at the end of the afterhyperpolarization phase

Part B. Two major components of an ion channel selectivity filter are _______ and _______. (assume Temp = 37 degrees Celcius)

a. pore length; diameter

b. pore length: charge distribution

c. charge distribution; diameter

d. hydration; pore length

Part C. A cell has 155 mM Potassium inside and 4.0 mM Potassium outside for Sodium the concentrations are 12 inside and 145 mM outside. Temperature is 37°C. The resting membrane potential of this cell is -3.05 mV, which means the relative permeability of sodium to potassium (b of the GHK-equation) is equal to:

a. 0.05 b. 0.50 c. 1.00 d. 1.05

Answer 1

The absolute refractory period of the action potential____________. (assume Temp = 37 degrees Celcius)

b. occurs because voltage-gated K+ channels have not recovered from inactivation

Two major components of an ion channel selectivity filter are _______ and _______. (assume Temp = 37 degrees Celcius)

c. charge distribution; diameter

A cell has 155 mM Potassium inside and 4.0 mM Potassium outside for Sodium the concentrations are 12 inside and 145 mM outside. Temperature is 37°C. The resting membrane potential of this cell is -3.05 mV, which means the relative permeability of sodium to potassium (b of the GHK-equation) is equal to:

a. 0.05