Question 1

Which of the following best describes the function of myelin in the nervous system?

Accepted Answer

Myelin increases the speed of action potential conduction by allowing the action potential to jump from node to node.

Question 2

A neuron receives multiple excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). What determines whether the neuron will fire an action potential?

Accepted Answer

The sum of all EPSPs and IPSPs at the cell body must reach the threshold potential.

Question 3

Which neurotransmitter is primarily released by the sympathetic division of the autonomic nervous system to prepare the body for 'fight-or-flight'?

Accepted Answer

Norepinephrine

Question 4

What is the main function of the hippocampus in the human brain?

Accepted Answer

Formation and consolidation of long-term memories

Question 5

During an action potential, the membrane potential of a neuron rapidly rises to approximately $$+50\ \mathrm{mV}$$ before returning to its resting value. What causes this rapid rise?

Accepted Answer

The opening of voltage-gated sodium ($$\mathrm{Na}^+) $$channels, allowing $$\mathrm{Na}^+ to $$enter the cell

Question 6

Which of the following best explains why damage to the left hemisphere of the cerebral cortex often results in language deficits?

Accepted Answer

The left hemisphere is dominant for speech, reading, writing, and language comprehension.

Question 7

A patient suffers a spinal cord injury that severs the cord at the thoracic level. Which of the following is the most likely consequence?

Accepted Answer

Loss of sensation and voluntary movement below the site of injury

Question 8

Which structure in the neuron is primarily responsible for receiving information from other neurons or the environment?

Accepted Answer

Dendrites

Question 9

Which of the following best describes the role of the thalamus in the brain?

Accepted Answer

It channels sensory information to the cerebral cortex, except for olfaction.

Question 10

Which of the following is a major difference between a nerve net (as in Hydra) and a centralized nervous system (as in vertebrates)?

Accepted Answer

A nerve net lacks a brain and has neurons distributed throughout the body, while a centralized nervous system has a brain and spinal cord.

Question 11

Which of the following best explains how the intensity of a stimulus is encoded by the nervous system?

Accepted Answer

By the frequency of action potentials and the number of neurons activated

Question 12

A person touches a hot stove and quickly withdraws their hand before feeling pain. Which neural pathway is responsible for this rapid response?

Accepted Answer

A reflex arc involving sensory neurons, interneurons in the spinal cord, and motor neurons

Question 13

Which neurotransmitter is most directly involved in stimulating skeletal muscle contraction at the neuromuscular junction?

Accepted Answer

Acetylcholine

Question 14

Which part of the brain is most crucial for coordinating smooth, accurate movements and is involved in motor learning?

Accepted Answer

Cerebellum

Question 15

Which of the following is a function of the limbic system?

Accepted Answer

Generating emotions and contributing to memory formation

Question 16

Which of the following best describes the blood-brain barrier?

Accepted Answer

A selective barrier formed by tightly joined capillary cells that restricts the passage of substances from the blood into the brain

Question 17

Which of the following scenarios best illustrates the concept of neural integration at the postsynaptic neuron?

Accepted Answer

A neuron receives both excitatory and inhibitory signals from multiple presynaptic neurons, and the sum of these signals determines whether it fires an action potential.

Question 18

Which of the following is a real-life example of the 'fight-or-flight' response mediated by the sympathetic nervous system?

Accepted Answer

A person’s heart rate increases and pupils dilate when startled by a loud noise.

Question 19

Which of the following best describes the function of interneurons in the nervous system?

Accepted Answer

They process information by connecting sensory and motor neurons within the central nervous system.

ch 39

Study Guide - Practice Questions

Study Guide - Flashcards