Q: During the resting membrane potential, which ion has the greatest influence on the membrane potential and why?

K\textsuperscript{+}, because the membrane is about 25 times more permeable to potassium than sodium.

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

Action potential arrives at axon terminal, Ca\textsuperscript{2+} enters, neurotransmitter is released, neurotransmitter binds to postsynaptic receptors.

Question 1

Which of the following best describes the main function of the Central Nervous System (CNS)?

Accepted Answer

It serves as the integrating and control center for processing and interpreting sensory input.

Question 2

A patient is experiencing difficulty with voluntary muscle movement but has no issues with involuntary functions such as heart rate. Which division of the nervous system is most likely affected?

Accepted Answer

Somatic nervous system

Question 3

Which type of neuroglia is responsible for forming the myelin sheath in the peripheral nervous system (PNS)?

Accepted Answer

Schwann cells

Question 4

A neuron is classified as multipolar if it has:

Accepted Answer

Three or more processes, including one axon and many dendrites

Question 5

Which of the following best explains why myelinated axons conduct impulses faster than unmyelinated axons?

Accepted Answer

Myelin sheath allows for saltatory conduction, where action potentials jump between nodes of Ranvier.

Question 6

During the resting membrane potential, which ion has the greatest influence on the membrane potential and why?

Accepted Answer

K	extsuperscript{+}, because the membrane is about 25 times more permeable to potassium than sodium.

Question 7

A local anesthetic blocks voltage-gated Na	extsuperscript{+} channels in a region of skin. What is the most immediate effect on the neurons in that area?

Accepted Answer

Action potentials cannot be generated, leading to loss of sensation.

Question 8

Which of the following equations correctly represents Ohm's Law as it applies to the movement of ions across a neuron's membrane?

Accepted Answer

$$I = V \div R$$

Question 9

A neuron receives two excitatory postsynaptic potentials (EPSPs) in rapid succession from the same presynaptic neuron. This is an example of:

Accepted Answer

Temporal summation

Question 10

Which neurotransmitter is most likely to cause hyperpolarization of the postsynaptic membrane, making it less likely to fire an action potential?

Accepted Answer

GABA

Question 11

A patient with multiple sclerosis (MS) is experiencing muscle weakness and visual disturbances. Which of the following best explains the underlying cause of these symptoms?

Accepted Answer

Autoimmune attack on CNS myelin sheaths, leading to slowed or blocked impulse conduction

Question 12

Which of the following is TRUE regarding the propagation of an action potential along an axon?

Accepted Answer

The action potential is regenerated at each segment of the axon, maintaining its size.

Question 13

Which of the following best describes the difference between graded potentials and action potentials?

Accepted Answer

Graded potentials decay with distance, while action potentials do not.

Question 14

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

Accepted Answer

Action potential arrives at axon terminal, Ca	extsuperscript{2+} enters, neurotransmitter is released, neurotransmitter binds to postsynaptic receptors.

Question 15

A person touches a hot stove and immediately withdraws their hand. This rapid, automatic response is an example of:

Accepted Answer

A spinal reflex arc

Question 16

Which type of neural circuit allows a single input to produce many outputs, such as activating multiple muscle groups during a reflex?

Accepted Answer

Diverging circuit

Question 17

Which of the following best describes the function of astrocytes in the CNS?

Accepted Answer

They regulate the chemical environment around neurons and facilitate exchange between neurons and capillaries.

Question 18

Which of the following statements about the sodium-potassium pump is correct?

Accepted Answer

It stabilizes the resting membrane potential by moving 3 Na	extsuperscript{+} out and 2 K	extsuperscript{+} in per ATP hydrolyzed.

Question 19

Which of the following best explains why a neuron cannot fire a second action potential during the absolute refractory period?

Accepted Answer

Voltage-gated Na	extsuperscript{+} channels are inactivated and cannot reopen.

Question 20

Which of the following is a characteristic of neurons that distinguishes them from most other cell types?

Accepted Answer

They are long-lived, amitotic, and have a high metabolic rate.

Fundamentals of the Nervous System and Nervous Tissue: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard