BIOD 322 NEUROSCIENCE
Neural Function and
Transmission
Latest Review Exam
Q&A
2024
,1. What is the primary role of myelin in neural transmission?
- A) To increase the speed of action potentials
- B) To prevent the action potentials
- C) To produce neurotransmitters
- D) To insulate the axon hillock
Answer: A) To increase the speed of action potentials
Rationale: Myelin is a fatty substance that insulates axons, allowing
electrical impulses to transmit quickly and efficiently along the nerve
cells.
2. Which ion's influx is most directly responsible for the depolarization
phase of an action potential?
- A) Sodium (Na+)
- B) Potassium (K+)
- C) Calcium (Ca2+)
- D) Chloride (Cl-)
Answer: A) Sodium (Na+)
Rationale: During depolarization, sodium channels open, allowing Na+
to flow into the neuron, causing the interior to become more positive.
3. What is the function of neurotransmitters in synaptic transmission?
- A) To generate electrical impulses in the post-synaptic neuron
- B) To carry electrical impulses across the synaptic cleft
- C) To modulate the strength of the signal sent to the post-synaptic
neuron
- D) To be reabsorbed by the pre-synaptic neuron
Answer: C) To modulate the strength of the signal sent to the post-
synaptic neuron
Rationale: Neurotransmitters bind to receptors on the post-synaptic
neuron to either stimulate or inhibit the generation of a new action
potential.
4. In a resting neuron, the concentration of which ion is typically higher
inside the cell compared to outside?
- A) Sodium (Na+)
- B) Potassium (K+)
- C) Calcium (Ca2+)
, - D) Chloride (Cl-)
Answer: B) Potassium (K+)
Rationale: Potassium ions are more concentrated inside the neuron at
rest, contributing to the resting membrane potential.
5. What is the significance of the sodium-potassium pump in maintaining
the resting membrane potential?
- A) It pumps sodium and potassium ions in equal quantities
- B) It pumps sodium ions out and potassium ions in, against their
concentration gradients
- C) It uses the energy from ATP to transport chloride ions
- D) It equalizes the concentration of ions across the membrane
Answer: B) It pumps sodium ions out and potassium ions in, against
their concentration gradients
Rationale: The sodium-potassium pump actively transports Na+ out of
the cell and K+ into the cell, which is essential for maintaining the resting
membrane potential.
6. What is an excitatory neurotransmitter?
- A) A neurotransmitter that decreases the likelihood of an action
potential in the post-synaptic neuron
- B) A neurotransmitter that increases the likelihood of an action
potential in the post-synaptic neuron
- C) A neurotransmitter that has no effect on the post-synaptic neuron
- D) A neurotransmitter that is only found in the central nervous system
Answer: B) A neurotransmitter that increases the likelihood of an action
potential in the post-synaptic neuron
Rationale: Excitatory neurotransmitters bind to receptors and increase
the chance that the post-synaptic neuron will fire an action potential.
7. What is the role of calcium ions at a chemical synapse?
- A) They initiate the repolarization phase of an action potential
- B) They are pumped out of the neuron by the sodium-potassium pump
- C) They trigger the release of neurotransmitters into the synaptic cleft
- D) They deactivate neurotransmitters in the synaptic cleft
Answer: C) They trigger the release of neurotransmitters into the
synaptic cleft
Rationale: Calcium ions enter the pre-synaptic neuron upon an action
Neural Function and
Transmission
Latest Review Exam
Q&A
2024
,1. What is the primary role of myelin in neural transmission?
- A) To increase the speed of action potentials
- B) To prevent the action potentials
- C) To produce neurotransmitters
- D) To insulate the axon hillock
Answer: A) To increase the speed of action potentials
Rationale: Myelin is a fatty substance that insulates axons, allowing
electrical impulses to transmit quickly and efficiently along the nerve
cells.
2. Which ion's influx is most directly responsible for the depolarization
phase of an action potential?
- A) Sodium (Na+)
- B) Potassium (K+)
- C) Calcium (Ca2+)
- D) Chloride (Cl-)
Answer: A) Sodium (Na+)
Rationale: During depolarization, sodium channels open, allowing Na+
to flow into the neuron, causing the interior to become more positive.
3. What is the function of neurotransmitters in synaptic transmission?
- A) To generate electrical impulses in the post-synaptic neuron
- B) To carry electrical impulses across the synaptic cleft
- C) To modulate the strength of the signal sent to the post-synaptic
neuron
- D) To be reabsorbed by the pre-synaptic neuron
Answer: C) To modulate the strength of the signal sent to the post-
synaptic neuron
Rationale: Neurotransmitters bind to receptors on the post-synaptic
neuron to either stimulate or inhibit the generation of a new action
potential.
4. In a resting neuron, the concentration of which ion is typically higher
inside the cell compared to outside?
- A) Sodium (Na+)
- B) Potassium (K+)
- C) Calcium (Ca2+)
, - D) Chloride (Cl-)
Answer: B) Potassium (K+)
Rationale: Potassium ions are more concentrated inside the neuron at
rest, contributing to the resting membrane potential.
5. What is the significance of the sodium-potassium pump in maintaining
the resting membrane potential?
- A) It pumps sodium and potassium ions in equal quantities
- B) It pumps sodium ions out and potassium ions in, against their
concentration gradients
- C) It uses the energy from ATP to transport chloride ions
- D) It equalizes the concentration of ions across the membrane
Answer: B) It pumps sodium ions out and potassium ions in, against
their concentration gradients
Rationale: The sodium-potassium pump actively transports Na+ out of
the cell and K+ into the cell, which is essential for maintaining the resting
membrane potential.
6. What is an excitatory neurotransmitter?
- A) A neurotransmitter that decreases the likelihood of an action
potential in the post-synaptic neuron
- B) A neurotransmitter that increases the likelihood of an action
potential in the post-synaptic neuron
- C) A neurotransmitter that has no effect on the post-synaptic neuron
- D) A neurotransmitter that is only found in the central nervous system
Answer: B) A neurotransmitter that increases the likelihood of an action
potential in the post-synaptic neuron
Rationale: Excitatory neurotransmitters bind to receptors and increase
the chance that the post-synaptic neuron will fire an action potential.
7. What is the role of calcium ions at a chemical synapse?
- A) They initiate the repolarization phase of an action potential
- B) They are pumped out of the neuron by the sodium-potassium pump
- C) They trigger the release of neurotransmitters into the synaptic cleft
- D) They deactivate neurotransmitters in the synaptic cleft
Answer: C) They trigger the release of neurotransmitters into the
synaptic cleft
Rationale: Calcium ions enter the pre-synaptic neuron upon an action
