Question 1

Which of the following best describes the function of astrocytes in the central nervous system?

Accepted Answer

They support and brace neurons, regulate exchanges between capillaries and neurons, and control the chemical environment.

Question 2

A patient presents with symptoms of muscle weakness and visual disturbances. MRI reveals hardened lesions in the CNS. Which process is most likely impaired?

Accepted Answer

Saltatory conduction in myelinated axons.

Question 3

Which equation correctly represents Ohm’s law as applied to neuronal membrane potentials?

Accepted Answer

$$V = I \ R$$

Question 4

During the repolarization phase of an action potential, which ion movement is primarily responsible for restoring the resting membrane potential?

Accepted Answer

Efflux of $$K^+$$ ions.

Question 5

Which structural class of neuron is most abundant in the human body and is the major neuron type in the CNS?

Accepted Answer

Multipolar neuron

Question 6

A local anesthetic blocks voltage-gated $$Na^+$$ channels. What is the immediate effect on neuronal function?

Accepted Answer

Action potentials cannot be generated, preventing nerve impulse transmission.

Question 7

Which of the following is TRUE regarding the sodium-potassium pump in neurons?

Accepted Answer

It pumps three $$Na^+$$ ions out and two $$K^+$$ ions in.

Question 8

Which type of glial cell is vital for regeneration of damaged peripheral nerve fibers?

Accepted Answer

Schwann cell

Question 9

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

Accepted Answer

Summation of all EPSPs and IPSPs to reach threshold at the axon hillock

Question 10

Which neurotransmitter is typically excitatory at neuromuscular junctions but inhibitory in cardiac muscle?

Accepted Answer

Acetylcholine

Question 11

Which of the following best describes saltatory conduction?

Accepted Answer

Action potentials jump from one node of Ranvier to the next, increasing conduction speed.

Question 12

Which of the following is a direct (fast) action of a neurotransmitter?

Accepted Answer

Binding directly to ligand-gated ion channels to alter membrane potential.

Question 13

Which of the following is NOT a function of microglial cells?

Accepted Answer

Forming myelin sheaths in the CNS.

Question 14

Which process is responsible for the termination of neurotransmitter effects at a chemical synapse?

Accepted Answer

All of the above.

Question 15

Which neural circuit pattern allows one input to be distributed to multiple outputs, such as in muscle coordination?

Accepted Answer

Diverging circuit

Question 16

Which of the following is TRUE about graded potentials?

Accepted Answer

They are short-lived, localized changes in membrane potential that decay with distance.

Question 17

Which ion is most responsible for establishing the resting membrane potential in neurons?

Accepted Answer

$$K^+$$

Question 18

Which of the following best explains the all-or-none phenomenon of action potentials?

Accepted Answer

If threshold is reached, an action potential is generated completely; if not, no action potential occurs.

Question 19

Which neurotransmitter is a potent inhibitor in the brain and its receptors are blocked by caffeine?

Accepted Answer

Adenosine

Question 20

Which of the following is a real-world consequence of opioid overdose, as described in the study materials?

Accepted Answer

Fatal suppression of breathing.

Fundamentals of the Nervous System and Nervous Tissue – Structured Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard