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2. When a neuron is polarized, it has:
A) more particles of a given charge on one side of the membrane than on the other
B) only positive particles passing through
C) a maximum reduction in refractive index
D) one end of the axon carrying a greater charge than the other

3. During resting potential the electrical gradient is:
A) more of a positive charge inside the neuron
B) an equally positive charge both inside and outside the neuron
C) a neuron with no charge
D) more of a negative charge inside the neuron

4. During resting potential, if a neuron was permeable to all ions equally, then
A) sodium would not enter at all
B) potassium would not be drawn back into the cell
C) sodium and potassium would enter and leave the cell at relatively equal rates
D) chloride would constantly leave

 5. In order for a neuron to fire it must first
A) depolarize
B) polarize
C) refract
D) myelinate

 6. Resting potential can be described as:
A) the neuron at rest, not spending any energy
B) a neuron poised and ready to fire
C) the neuron's membrane impermeable to all ions
D) the rest of the neuron's potential after it has fired

7. During resting potential:
A) there is more of a concentration gradient than an electrical gradient
B) there is more of an electrical gradient than a concentration gradient
C) an equilibrium is maintained between the concentration and electrical gradients
D) neither the concentration nor the electrical gradients are important

 8. The sodium potassium pump works to:
A) transport sodium into the neuron while taking chloride out
B) transport three sodium out of the neuron for every two potassium it brings back in
C) transports calcium into the neuron so the neurotransmitter can get out
D) pump the waste products out of the cell

 9. Besides the action of the sodium/potassium pump, the ion whose outflux is most important in re-establishing the resting potential is:
A) potassium
B) sodium
C) chloride
D) calcium

 10. The reason that the neuron will expend energy through the action of the sodium-potassium pump is that:
A) sodium is harder to transport in than it is to get out of the neuron
B) potassium doesn't pass out of the neuron because the gates to potassium are closed
C) maintaining the concentration gradient and the electrical graident is the way in which the neuron prepare for quick action
D) it's easier to burn calories in the brain this way

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