Q: Which of the following equations correctly represents the conversion of ATP to cAMP by adenylate cyclase during G protein signaling?

$$\mathrm{ATP} \xrightarrow{\text{adenylate cyclase}} \mathrm{cAMP} + 2\mathrm{P}_i$$

Question 1

Which of the following best describes the main structural difference between chemical and electrical synapses?

Accepted Answer

Chemical synapses have a synaptic cleft and use neurotransmitters, while electrical synapses have gap junctions that directly connect the cytoplasm of adjacent neurons.

Question 2

A patient is given a drug that inhibits acetylcholinesterase (AChE). What is the most likely effect at a cholinergic synapse?

Accepted Answer

The neurotransmitter acetylcholine will accumulate in the synaptic cleft, prolonging depolarization of the postsynaptic membrane.

Question 3

Which neurotransmitter is most commonly associated with inhibitory postsynaptic potentials (IPSPs) in the adult brain?

Accepted Answer

GABA (gamma-aminobutyric acid)

Question 4

What is the primary mechanism by which norepinephrine (NE) produces its effects at an excitatory adrenergic synapse?

Accepted Answer

Activation of G protein–coupled receptors leading to increased cyclic AMP (cAMP) production

Question 5

Which of the following equations correctly represents the conversion of ATP to cAMP by adenylate cyclase during G protein signaling?

Accepted Answer

$$\mathrm{ATP} \xrightarrow{	ext{adenylate cyclase}} \mathrm{cAMP} + 2\mathrm{P}_i$$

Question 6

A neuron receives simultaneous EPSPs from three different presynaptic neurons. What type of summation is this?

Accepted Answer

Spatial summation

Question 7

Which of the following best explains why synaptic delay is considered the rate-limiting step of neural transmission?

Accepted Answer

It takes time for neurotransmitter to be released, diffuse across the synaptic cleft, and bind to receptors.

Question 8

Which of the following is a correct statement about the effect of neurotransmitters?

Accepted Answer

The effect of a neurotransmitter depends on the receptor to which it binds.

Question 9

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

Accepted Answer

A local hyperpolarization that moves the neuron farther from threshold

Question 10

Which of the following is a real-life example of a diverging neural circuit?

Accepted Answer

A single neuron in the brain activating multiple motor neurons in the spinal cord, leading to contraction of many muscle fibers

Question 11

Which of the following neurotransmitters is classified as a peptide and is known to reduce pain perception?

Accepted Answer

Beta-endorphin

Question 12

A neuron is exposed to a neuromodulator that increases the sensitivity of postsynaptic receptors to glutamate. What is the most likely effect?

Accepted Answer

The postsynaptic neuron will be more likely to reach threshold and fire an action potential.

Question 13

Which of the following best describes the function of astrocytes in synapse development?

Accepted Answer

They provide physical support and cholesterol needed for synapse construction.

Question 14

Which of the following is a correct sequence of events at a chemical synapse?

Accepted Answer

Action potential arrives at axon terminal → Voltage-gated Ca2+ channels open → Neurotransmitter is released → Neurotransmitter binds to receptors

Question 15

Which of the following best explains why long-term potentiation (LTP) is important in the nervous system?

Accepted Answer

LTP increases synaptic strength, which is believed to underlie learning and memory.

Question 16

Which of the following is true regarding the termination of neurotransmitter effects at a synapse?

Accepted Answer

Neurotransmitter effects are terminated by reuptake, enzymatic degradation, or diffusion away from the synaptic cleft.

Question 17

Which of the following best describes the role of endocannabinoids in the nervous system?

Accepted Answer

They are lipid-soluble neurotransmitters that act at G protein–coupled receptors and are involved in learning, memory, and appetite regulation.

Question 18

A patient has a mutation that prevents the formation of gap junctions in neurons. Which type of synaptic transmission would be most affected?

Accepted Answer

Electrical synaptic transmission

Question 19

Which of the following is a characteristic of parallel processing in neural circuits?

Accepted Answer

Input travels along several pathways, allowing different parts of the brain to process information simultaneously.

The Synapse: Structure, Function, and Integration in the Nervous System

Study Guide - Practice Questions

Study Guide - Flashcards