Assume a neuron's membrane potential is -60 mV, what's the net consequence on the membrane potential of a 5 picoamp (pA) sodium current that occurs simultaneously with a 5 pA chloride current? a. There's a 5 pA hyperpolarizing current b. There's a 10 pA depolarizing current c. There's a 10 pA hyperpolarizing current d. There's a 5 pA depolarizing current e. There's no change in the membrane potential

What is the intracellular voltage for Cl- if the intracellular concentration was 5 mM and the extracellular concentration was 130 mM. Write the voltage as a number in mV inside the cell relative to that outside, eg. -72 or + 90. Question 2. What is the intracellular voltage for Ca++ if the intracellular concentration was 0.0008 mM and the extracellular concentration was 0.6 mM. Write the voltage as a number in mV inside the cell relative to that outside, eg. -72 or +90. Round to the nearest milli Volt.

Consider a typical mammalian neuron with all of the appropriate membrane channels. If you know that neuron is at rest, at a temperature of 37°C and you know the intracellular and extracellular concentration of the potassium, which of the following statements is most likely to be true? a. The equilibrium potential of potassium would be negative if the concentration of potassium is higher on the inside. b. The equilibrium potential of potassium would be positive if the concentration of potassium is higher on the inside c. The equilibrium potential of potassium cannot be calculated because the Nernst equation requires that you know the concentration of all ions d. The equilibrium potential of potassium be zero if the concentration of potassium is higher on the outside e. None of the above

Graded potentials in neurons:   Question 5 options:   a. Graded potentials that result from an influx of chloride ions are always hyperpolarizing.   b. Graded potentials can undergo both spatial and temporal summation.   c. The initiation of a graded potential can only occur after the cell membrane depolarizes to threshold (about -55 mV).   d. Both a) and b) are correct and c) is incorrect   e. Statements a), b) and c) are all correct