Question 1

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

Accepted Answer

Selective permeability allows more potassium ions to leave the cell than sodium ions to enter.

Question 2

A patient is exposed to a toxin that prolongs the opening of chloride channels in their neurons. What is the most likely effect on action potential generation?

Accepted Answer

It will hyperpolarize the neuron, making it less likely to generate action potentials.

Question 3

Which statement best describes the 'all-or-none' principle of action potentials?

Accepted Answer

Once threshold is reached, an action potential of fixed size is generated.

Question 4

During the relative refractory period, which of the following is true about the neuron's ability to fire another action potential?

Accepted Answer

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

Question 5

Which of the following best describes the function of pacemaker cells in cardiac muscle?

Accepted Answer

They spontaneously generate action potentials that regulate the heartbeat.

Question 6

A person touches a hot stove and immediately withdraws their hand. Which type of sensory receptor is primarily responsible for detecting this painful stimulus?

Accepted Answer

Nociceptors

Question 7

Which of the following scenarios best illustrates the function of tonic receptors?

Accepted Answer

You continue to feel the pressure of a watch on your wrist throughout the day.

Question 8

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

Accepted Answer

A postsynaptic potential that varies in magnitude depending on the amount of neurotransmitter released.

Question 9

Damage to which cranial nerve would most likely result in loss of the sense of smell?

Accepted Answer

Olfactory nerve

Question 10

Which of the following best explains why the brain allocates more space to the sensory cortex for the hands than for the back?

Accepted Answer

The hands have a higher density of sensory receptors, requiring more cortical processing area.

Question 11

A patient with a myocardial infarction (heart attack) reports pain in their left arm. This is an example of:

Accepted Answer

Referred pain

Question 12

Which of the following best describes the role of the sodium-potassium pump in maintaining the resting membrane potential?

Accepted Answer

It actively transports sodium ions out of the cell and potassium ions into the cell, maintaining concentration gradients.

Question 13

Which of the following is a characteristic of phasic receptors?

Accepted Answer

They adapt rapidly to a constant stimulus and stop responding.

Question 14

If the extracellular potassium concentration increases significantly, what effect would this have on the resting membrane potential?

Accepted Answer

The resting membrane potential would become less negative (depolarized).

Question 15

Which of the following best describes the function of mechanoreceptors?

Accepted Answer

They detect mechanical pressure or distortion, such as touch or vibration.

Question 16

A neuron receives multiple subthreshold excitatory postsynaptic potentials (EPSPs) in rapid succession at the same synapse. What is this process called?

Accepted Answer

Temporal summation

Question 17

Which of the following is true regarding the absolute refractory period of a neuron?

Accepted Answer

No stimulus, no matter how strong, can generate another action potential during this period.

Question 18

Which of the following best explains why action potentials travel in only one direction along an axon?

Accepted Answer

The refractory period prevents the action potential from traveling backward.

Question 19

Which of the following best describes the function of chemoreceptors?

Accepted Answer

They detect changes in chemical composition, such as oxygen or carbon dioxide levels.

Question 20

A person enters a dark room and, after several minutes, is able to see better. Which type of sensory receptor adaptation is most responsible for this change?

Accepted Answer

Sensory receptor upregulation

Resting Membrane Potential and Neural Signaling

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