Q: Which equation is used to calculate the equilibrium potential for an ion across a membrane?

$$E = \frac{RT}{zF} \ln \left( \frac{[\text{ion}]_{\text{out}}}{[\text{ion}]_{\text{in}}} \right)$$

Question 1

Which of the following best describes the primary function of glial cells in the central nervous system?

Accepted Answer

They provide structural support, insulation, nutrient supply, and help maintain ion homeostasis.

Question 2

The resting membrane potential ($$V_m) of a $$neuron is primarily determined by which of the following?

Accepted Answer

The membrane's permeability to potassium ions ($$K^+).$$

Question 3

Which equation is used to calculate the equilibrium potential for an ion across a membrane?

Accepted Answer

$$E = \frac{RT}{zF} \ln \left( \frac{[	ext{ion}]_{	ext{out}}}{[	ext{ion}]_{	ext{in}}} ight)$$

Question 4

A neuron receives simultaneous excitatory and inhibitory inputs. Which process determines whether an action potential will be generated?

Accepted Answer

Integration of both spatial and temporal summation at the axon hillock.

Question 5

Which neurotransmitter is most commonly associated with excitatory synapses in the central nervous system?

Accepted Answer

Glutamate

Question 6

What is the effect of opening chloride ($$Cl^-) $$channels in the postsynaptic membrane?

Accepted Answer

It hyperpolarizes the membrane, producing an IPSP.

Question 7

Why do myelinated axons conduct action potentials faster than unmyelinated axons?

Accepted Answer

Myelin reduces ion leakage and allows saltatory conduction between nodes of Ranvier.

Question 8

Which of the following is NOT a mechanism for stopping the synaptic signal?

Accepted Answer

Continuous release of neurotransmitter from the presynaptic cell.

Question 9

In the knee-jerk reflex, which type of neuron is responsible for transmitting the sensory signal to the spinal cord?

Accepted Answer

Sensory neuron

Question 10

Which of the following statements about action potentials is TRUE?

Accepted Answer

Action potentials are 'all-or-none' digital signals with consistent peak height and duration.

Question 11

A neuron is poisoned with a drug that inhibits the Na+/K+ pump. What will happen to the resting membrane potential ($$V_m) $$immediately after poisoning?

Accepted Answer

$$V_m$$ will remain at its resting value for a long time.

Question 12

Which of the following best explains why giant axons in invertebrates can conduct action potentials rapidly without myelin?

Accepted Answer

Their large diameter reduces resistance and allows faster passive current flow.

Question 13

Which of the following neurotransmitters is generally inhibitory in the central nervous system?

Accepted Answer

Serotonin

Question 14

Which type of synapse allows for direct electrical communication between neurons and cannot be easily modulated?

Accepted Answer

Electrical synapse mediated by gap junctions

Question 15

Which of the following is a real-world consequence of synaptic loss in the human brain?

Accepted Answer

Progression of Alzheimer's disease correlates with loss of synapses

Question 16

Which of the following best describes the function of the axon hillock in a neuron?

Accepted Answer

It integrates excitatory and inhibitory inputs to determine if an action potential will be fired.

Question 17

Which of the following is a characteristic of metabotropic receptors?

Accepted Answer

They are G protein-coupled and activate second messenger pathways.

Question 18

Which of the following best describes the effect of acetylcholine (ACh) at the neuromuscular junction?

Accepted Answer

ACh opens a Na+ channel, depolarizing the postsynaptic membrane and triggering muscle contraction.

Question 19

Which of the following is TRUE regarding spatial summation?

Accepted Answer

It involves the summing of inputs from different synapses at the same time.

Introduction to Neurobiology: Structure and Function of Nervous Systems

Study Guide - Practice Questions

Study Guide - Flashcards