Question 1

Which of the following best explains why the resting membrane potential of a neuron is typically negative?

Accepted Answer

The cell membrane is more permeable to potassium ions, allowing more positive charge to leave the cell.

Question 2

A patient is experiencing referred pain in their left arm during a heart attack. Which of the following best describes this phenomenon?

Accepted Answer

Pain signals from the heart are interpreted as coming from the arm due to shared neural pathways.

Question 3

Which of the following statements about action potentials is correct?

Accepted Answer

Action potentials follow the all-or-none principle once threshold is reached.

Question 4

During the relative refractory period of a neuron, which of the following is true?

Accepted Answer

A stronger-than-normal stimulus is required to trigger another action potential.

Question 5

Which cell type is primarily responsible for maintaining the blood-brain barrier?

Accepted Answer

Astrocytes

Question 6

A researcher is studying a receptor that continuously responds to a prolonged stimulus, such as light in the eye. What type of receptor is this?

Accepted Answer

Tonic receptor

Question 7

Which of the following best describes the function of the sodium-potassium pump in neurons?

Accepted Answer

It actively transports sodium ions out of the cell and potassium ions into the cell, helping maintain the resting membrane potential.

Question 8

Which cranial nerve is purely sensory and responsible for vision?

Accepted Answer

Optic nerve

Question 9

A neuron is exposed to a drug that keeps potassium channels open longer than normal after an action potential. What is the most likely effect on the neuron's excitability?

Accepted Answer

The neuron will become hyperpolarized and less likely to fire another action potential.

Question 10

Which of the following best explains why the lips and hands have a larger representation in the somatosensory cortex than the back or legs?

Accepted Answer

They receive more sensory input due to a higher density of sensory receptors.

Question 11

Which of the following equations can be used to estimate the resting membrane potential of a neuron based on potassium ion concentrations?

Accepted Answer

$$V_m = \frac{RT}{F} \ln \left( \frac{[K^+]_{out}}{[K^+]_{in}} \right)$$

Question 12

Which of the following is an example of a graded potential?

Accepted Answer

A postsynaptic potential in a dendrite

Question 13

A patient with dehydration has increased activity in osmoreceptors. What physiological response is most likely to occur as a result?

Accepted Answer

Increased thirst sensation

Question 14

Which of the following best describes the function of free nerve endings?

Accepted Answer

They are responsible for detecting changes in temperature and pain.

Question 15

Which of the following scenarios best illustrates the all-or-none principle of action potentials?

Accepted Answer

A neuron fires an action potential only if the threshold is reached, regardless of stimulus strength above threshold.

Question 16

Which of the following is a unique property of pacemaker cells in the heart compared to typical neurons?

Accepted Answer

They can spontaneously generate action potentials without external input.

Question 17

A person touches a hot stove and immediately withdraws their hand. Which neural structure is primarily responsible for detecting the temperature change?

Accepted Answer

Free nerve endings

Question 18

Which of the following best describes the role of the pyramidal tract?

Accepted Answer

It is responsible for voluntary motor control, especially fine movements.

Question 19

Which of the following would most likely result from a loss of function in astrocytes?

Accepted Answer

Disruption of the blood-brain barrier and altered regulation of blood flow in the brain

Question 20

A neuron receives several subthreshold stimuli in rapid succession, resulting in a depolarization that reaches threshold and triggers an action potential. Which concept does this scenario best illustrate?

Accepted Answer

Temporal summation of graded potentials

Resting Membrane Potential and Neural Signaling: Key Concepts for GOB Chemistry

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