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 a higher concentration of negative ions inside the cell.

Question 2

During the generation of an action potential, which event occurs first after the membrane reaches threshold?

Accepted Answer

Sodium channels open, allowing $$Na^+ to $$enter the cell.

Question 3

Which of the following best explains why myelinated axons conduct action potentials faster than unmyelinated axons?

Accepted Answer

Myelin allows action potentials to jump from node to node (saltatory conduction).

Question 4

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.

Question 5

Which of the following is an example of spatial summation in neuronal integration?

Accepted Answer

Multiple presynaptic neurons fire at the same time onto a single postsynaptic neuron.

Question 6

Which of the following correctly matches the region of the central nervous system (CNS) with its function?

Accepted Answer

Thalamus – acts as a relay station for sensory information.

Question 7

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

Accepted Answer

Inhibitory postsynaptic potential (IPSP)

Question 8

Which of the following best describes the 'all-or-none' property of action potentials?

Accepted Answer

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

Question 9

A patient is given a drug that prolongs the opening of GABA-activated ion channels. What is the most likely effect on the postsynaptic neuron?

Accepted Answer

Longer or larger inhibitory postsynaptic potentials (IPSPs).

Question 10

Which of the following sequences correctly represents the order of events in synaptic transmission?

Accepted Answer

Depolarization of presynaptic membrane → neurotransmitter release → stimulation of postsynaptic receptors → opening of ion channels

Question 11

Which of the following best describes temporal summation?

Accepted Answer

A single presynaptic neuron fires multiple times in rapid succession.

Question 12

What is the main function of the nodes of Ranvier in a myelinated axon?

Accepted Answer

They allow action potentials to be regenerated, enabling saltatory conduction.

Question 13

Which of the following is a correct statement about the difference in ion distribution across the neuronal membrane at rest?

Accepted Answer

There is a higher concentration of $$K^+$$ inside the cell and a higher concentration of $$Na^+$$ outside the cell.

Question 14

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

Accepted Answer

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

Question 15

Which of the following best describes the process of reuptake in synaptic transmission?

Accepted Answer

Neurotransmitters are taken back into the presynaptic neuron for reuse.

Question 16

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

Accepted Answer

Regulating heart rate and breathing.

Question 17

If a neuron is exposed to a toxin that blocks voltage-gated sodium channels, what will be the immediate effect on action potential generation?

Accepted Answer

Action potentials will not be generated because depolarization cannot occur.

Question 18

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

Accepted Answer

They bind to receptors on the postsynaptic membrane to open ion channels.

Question 19

Which of the following is an example of convergence in neural circuits?

Accepted Answer

Multiple neurons send signals to a single postsynaptic neuron.

Question 20

A patient with multiple sclerosis has damaged myelin sheaths. Which of the following symptoms is most likely to result from this damage?

Accepted Answer

Slower or blocked propagation of action potentials.

Information Transmission in the Nervous System: Foundations for Motor Control

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