Q: Which equation correctly represents the action of the Na+/K+ pump?

$$\text{ATP} + 3\ \mathrm{Na}^+_{\text{in}} + 2\ \mathrm{K}^+_{\text{out}} \rightarrow 3\ \mathrm{Na}^+_{\text{out}} + 2\ \mathrm{K}^+_{\text{in}} + \text{ADP} + \text{P}_i$$

Question 1

Which of the following best describes the role of the Na+/K+ pump in maintaining the resting membrane potential of a neuron?

Accepted Answer

It uses ATP to move 3 Na+ out of the cell and 2 K+ into the cell, maintaining concentration gradients.

Question 2

A patient suffers a spinal cord injury. Which glial cell type would be most responsible for forming scar tissue that inhibits axon regeneration in the CNS?

Accepted Answer

Astrocyte

Question 3

During the rising phase of an action potential, which ion movement is primarily responsible for the change in membrane voltage?

Accepted Answer

Na+ enters the cell through voltage-gated channels.

Question 4

Which equation correctly represents the action of the Na+/K+ pump?

Accepted Answer

$$	ext{ATP} + 3\ \mathrm{Na}^+_{	ext{in}} + 2\ \mathrm{K}^+_{	ext{out}} ightarrow 3\ \mathrm{Na}^+_{	ext{out}} + 2\ \mathrm{K}^+_{	ext{in}} + 	ext{ADP} + 	ext{P}_i$$

Question 5

Which structural neuron type is most likely to be found in the retina and olfactory epithelium?

Accepted Answer

Bipolar neuron

Question 6

A neurotransmitter binds to a metabotropic receptor on the postsynaptic membrane. Which of the following best describes the resulting effect?

Accepted Answer

A G-protein is activated, leading to slower, longer-lasting intracellular signaling.

Question 7

Which sequence correctly describes the steps of chemical synaptic transmission?

Accepted Answer

Action potential arrives → voltage-gated Ca2+ channels open → synaptic vesicles release neurotransmitter → neurotransmitter binds postsynaptic receptor → postsynaptic potential occurs

Question 8

Which neurotransmitter is the major inhibitory transmitter in the spinal cord?

Accepted Answer

Glycine

Question 9

A neuron receives multiple EPSPs and IPSPs from different presynaptic neurons at the same time. This process is best described as:

Accepted Answer

Spatial summation

Question 10

Which of the following best explains why saltatory conduction is faster than continuous conduction?

Accepted Answer

Myelin reduces current leakage, allowing the action potential to jump between nodes of Ranvier.

Question 11

Which glial cell is responsible for myelinating axons in the PNS and also supports axon repair?

Accepted Answer

Schwann cell

Question 12

A neuron is at rest with a membrane potential of $$-70\ \mathrm{mV}. If it $$depolarizes to $$-60\ \mathrm{mV}$$, which of the following statements is correct?

Accepted Answer

The neuron is moving closer to threshold and is more likely to fire an action potential.

Question 13

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

Accepted Answer

No stimulus can trigger another action potential because Na+ channels have not reset.

Question 14

Which circuit pattern allows one input neuron to distribute information to multiple targets, such as amplifying a sensory signal?

Accepted Answer

Diverging circuit

Question 15

Which neurotransmitter is synthesized from choline and acetyl-CoA, and is broken down by acetylcholinesterase?

Accepted Answer

Acetylcholine (ACh)

Question 16

A neuron receives repeated rapid input from a single presynaptic neuron, resulting in summation of postsynaptic potentials. This is best described as:

Accepted Answer

Temporal summation

Question 17

Which of the following best describes the effect of an inhibitory postsynaptic potential (IPSP)?

Accepted Answer

It hyperpolarizes the postsynaptic membrane, decreasing the likelihood of firing.

Question 18

Which of the following is a major excitatory neurotransmitter in the brain?

Accepted Answer

Glutamate

Question 19

Which neuron structure is primarily responsible for receiving input and carrying local electrical changes toward the cell body?

Accepted Answer

Dendrite

Question 20

A patient is exposed to a neurotoxin that blocks voltage-gated Ca2+ channels in axon terminals. Which process would be directly impaired?

Accepted Answer

Release of neurotransmitter into the synaptic cleft

Chapter 11: Introduction to the Nervous System and Nervous Tissue – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard