Question 1

Which of the following best describes an excitatory postsynaptic potential (EPSP)?

Accepted Answer

It is produced by the influx of Na$$^+$$ ions, leading to depolarization of the postsynaptic membrane.

Question 2

Which statement correctly compares graded potentials and action potentials?

Accepted Answer

Graded potentials decrease in amplitude with distance, while action potentials remain constant in amplitude.

Question 3

A neuron receives simultaneous excitatory and inhibitory inputs at different locations on its membrane. What is this process called?

Accepted Answer

Spatial summation

Question 4

Which of the following would most likely increase the conduction velocity of an action potential along an axon?

Accepted Answer

Increasing the degree of myelination

Question 5

Multiple sclerosis (MS) primarily affects which structure, leading to symptoms such as muscle weakness and speech disturbances?

Accepted Answer

Myelin sheaths in the central nervous system

Question 6

Which equation best represents the relationship between membrane potential change ($$	riangle V$$), current ($$I$$), and resistance ($$R) in a $$neuron?

Accepted Answer

$$	riangle V = I 	imes R$$

Question 7

Which type of neurotransmitter receptor is directly associated with an ion channel and produces immediate, brief effects?

Accepted Answer

Ionotropic receptor

Question 8

A patient is given a drug that blocks muscarinic acetylcholine receptors. Which effect would most likely be observed?

Accepted Answer

Reduced parasympathetic activity, such as decreased gland secretion

Question 9

Which of the following is true regarding the summation of postsynaptic potentials?

Accepted Answer

EPSPs and IPSPs can summate, and their combined effect determines whether the postsynaptic neuron reaches threshold.

Question 10

Which neurotransmitter is most associated with the 'fight or flight' response and acts primarily through metabotropic receptors?

Accepted Answer

Norepinephrine

Question 11

If a postsynaptic neuron receives two EPSPs in rapid succession at the same synapse, what is this process called?

Accepted Answer

Temporal summation

Question 12

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

Accepted Answer

Myelin allows action potentials to jump between nodes of Ranvier, a process called saltatory conduction.

Question 13

Which of the following is a property of action potentials but NOT graded potentials?

Accepted Answer

All-or-none response

Question 14

A neuron is exposed to a neurotransmitter that opens Cl$$^-$$ channels in its membrane. What is the most likely effect?

Accepted Answer

Hyperpolarization and decreased likelihood of action potential

Question 15

Which of the following best describes the role of G-protein coupled (metabotropic) receptors in neurotransmission?

Accepted Answer

They activate second messenger systems, leading to indirect, prolonged effects.

Question 16

Which neurotransmitter is most likely to cause depolarization through ionotropic receptors in the CNS?

Accepted Answer

Glutamate

Question 17

A patient with MS experiences slowed nerve conduction. Which equation best explains the effect of increased membrane resistance due to loss of myelin?

Accepted Answer

$$v = \frac{1}{\sqrt{R}}$$

Question 18

Which of the following is a direct effect of activating muscarinic acetylcholine receptors in the heart?

Accepted Answer

Decreased heart rate

Question 19

Which property of graded potentials allows them to influence the likelihood of action potential generation?

Accepted Answer

They can be summed spatially and temporally.

Question 20

Which neurotransmitter is most likely to cause hyperpolarization through ionotropic Cl$$^-$$ channels?

Accepted Answer

GABA

Lecture #15

Guida di studio - Domande di pratica

Study guide - Flashcard