Question 1

Which of the following best describes the movement of potassium ions (K+) through a K+ leak channel in a neuron at rest?

Accepted Answer

K+ ions move out of the cell due to the concentration gradient, but the electrical gradient opposes this movement.

Question 2

Suppose the extracellular fluid has a chloride (Cl-) concentration of 120 mM, while the cytosol has a Cl- concentration of 60 mM, and the cytosol is more negative than the extracellular fluid. Which statement is correct regarding the movement of Cl- ions?

Accepted Answer

The concentration gradient favors a net movement out of the cell, the electrical gradient favors movement into the cell.

Question 3

Which of the following is true regarding sodium (Na+) and potassium (K+) concentrations in a neuron at rest?

Accepted Answer

The concentration of sodium is higher outside the cell than inside, whereas the concentration of potassium is greater inside the cell than outside.

Question 4

What is the primary function of the sodium-potassium pump (Na+/K+ ATPase) in neurons?

Accepted Answer

It transports 2 potassium ions into the cell and ejects 3 sodium ions.

Question 5

If the sodium-potassium pump is blocked by a toxin, what will happen to the concentration of potassium inside the neuron over time?

Accepted Answer

The concentration of potassium will decrease.

Question 6

Which of the following best describes the change in membrane potential from -90 mV to -10 mV in a neuron?

Accepted Answer

Depolarization.

Question 7

Which of the following statements about graded potentials is FALSE?

Accepted Answer

Graded potentials occur mainly in axons.

Question 8

A neuron receives 13 EPSPs of 2 mV each and 2 IPSPs of 3 mV each at the trigger zone. If the resting membrane potential is -70 mV and the threshold is -55 mV, will an action potential be generated?

Accepted Answer

Yes, because the net depolarization reaches threshold.

Question 9

During the relative refractory period, a larger-than-normal depolarizing stimulus can:

Accepted Answer

Bring the membrane to threshold and initiate a second action potential.

Question 10

Which of the following best describes saltatory conduction in myelinated axons?

Accepted Answer

Action potentials are generated only at the nodes of Ranvier.

Question 11

Which of the following brain regions is NOT involved in maintaining routine, homeostatic activity?

Accepted Answer

The prefrontal cortex.

Question 12

Which of the following is the primary functional difference between the somatic nervous system (SNS) and autonomic nervous system (ANS)?

Accepted Answer

The SNS controls voluntary muscle, the ANS controls involuntary muscle.

Question 13

Which of the following statements about the sympathetic and parasympathetic divisions of the ANS is true?

Accepted Answer

The sympathetic division is responsible for an increase in heart rate.

Question 14

Which of the following best explains why the sympathetic nervous system causes decreased activity in the digestive tract?

Accepted Answer

During sympathetic activation, energy is required elsewhere in the body for more 'essential' functions.

Question 15

Which neurotransmitters are the major ones released by autonomic nervous system neurons?

Accepted Answer

Acetylcholine; norepinephrine.

Question 16

Where would you find a cholinergic nicotinic receptor in the autonomic nervous system?

Accepted Answer

At the synapse between a preganglionic and postganglionic fiber.

Question 17

Which of the following is a function of the basal nuclei?

Accepted Answer

Regulating the start and stop of movements.

Question 18

Which of the following diseases is most likely to result from dysfunction of the basal nuclei?

Accepted Answer

Parkinson’s Disease.

Question 19

Which of the following best describes the role of reciprocal inhibition in the stretch reflex?

Accepted Answer

It allows for smooth movement of extensor and flexor muscles.

Question 20

Which of the following best describes the pathway for an impulse in the sympathetic nervous system?

Accepted Answer

Spinal cord \u003e preganglionic fiber \u003e ganglion \u003e postganglionic fiber \u003e effector

Study Guidance for ANP Nervous System: Ions, Gradients, and Membrane Potentials

Study Guide - Practice Questions

Study Guide - Flashcards