Question 1

Which of the following best describes the resting membrane potential of a typical neuron?

Accepted Answer

It is approximately $$-70\ \mathrm{mV}$$ due to more negative ions inside the cell compared to outside.

Question 2

What is the primary function of myelin in the nervous system?

Accepted Answer

To allow faster conduction of nerve impulses by enabling action potentials to jump between nodes of Ranvier.

Question 3

During the generation of an action potential, which event occurs first?

Accepted Answer

Depolarization due to the influx of sodium ions ($$\mathrm{Na}^+).$$

Question 4

Which of the following best explains the 'all-or-none' principle of action potentials?

Accepted Answer

Once the threshold is reached, an action potential is always generated with the same amplitude.

Question 5

A drug that blocks the reuptake of dopamine in the synaptic cleft would most likely have which effect?

Accepted Answer

Increase the amount of dopamine available to bind to postsynaptic receptors, enhancing transmission.

Question 6

Which of the following is a correct sequence of events in synaptic transmission?

Accepted Answer

Action potential arrives at axon terminal → Depolarization of presynaptic membrane → Release of neurotransmitters → Stimulation of postsynaptic receptors

Question 7

Which of the following best describes spatial summation in neuronal integration?

Accepted Answer

Inputs from many presynaptic neurons occurring at the same time, combining their effects on the postsynaptic neuron.

Question 8

If a postsynaptic potential hyperpolarizes the membrane, making it more negative, what is this called?

Accepted Answer

Inhibitory postsynaptic potential (IPSP)

Question 9

Which of the following is NOT a function of the thalamus?

Accepted Answer

Initiating voluntary muscle contractions.

Question 10

A patient is given a drug that prolongs the opening of inhibitory ion channels on the postsynaptic membrane. What is the most likely effect on neuronal activity?

Accepted Answer

Decreased likelihood of action potential generation due to longer or larger IPSPs.

Question 11

Which of the following best describes the role of neurotransmitters at the synapse?

Accepted Answer

They open or close ion channels on the postsynaptic membrane, influencing membrane potential.

Question 12

Which of the following is a correct description of the difference between the central and peripheral nervous systems?

Accepted Answer

The central nervous system includes the brain and spinal cord, while the peripheral nervous system includes peripheral nerves and ganglia.

Question 13

Which of the following best explains why action potentials travel faster in myelinated axons compared to unmyelinated axons?

Accepted Answer

Action potentials jump from one node of Ranvier to the next, a process called saltatory conduction.

Question 14

A neuron receives both excitatory and inhibitory inputs. What determines whether it will generate an action potential?

Accepted Answer

The sum of all excitatory and inhibitory postsynaptic potentials at the axon hillock.

Question 15

Which of the following is an example of temporal summation?

Accepted Answer

A single presynaptic neuron firing multiple times in rapid succession.

Question 16

Which of the following best describes the function of interneurons?

Accepted Answer

They connect sensory and motor neurons within the central nervous system.

Question 17

If the membrane potential of a neuron changes from $$-70\ \mathrm{mV} to$$ $$-60\ \mathrm{mV}$$, what has occurred?

Accepted Answer

The neuron has depolarized.

Question 18

Which of the following is a correct pairing of nervous system region and function?

Accepted Answer

Medulla – controls basic life functions such as breathing and heart rate

Question 19

Which of the following best describes the process of reuptake at the synapse?

Accepted Answer

Neurotransmitters are taken back into the presynaptic neuron for reuse.

Question 20

A person consumes a drug that blocks inhibitory postsynaptic potentials (IPSPs). What is the most likely effect on their nervous system?

Accepted Answer

Increased likelihood of uncontrolled neuronal firing and possible seizures.

Information Transmission in the Nervous System: Foundations for Motor Control

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