Question 1

Which of the following best describes the difference between REM sleep and deep sleep as observed in EEG brain waves?

Accepted Answer

REM sleep shows low amplitude, high frequency waves similar to wakefulness, while deep sleep shows high amplitude, low frequency waves.

Question 2

Why does cutting sleep short most significantly impact REM sleep?

Accepted Answer

REM sleep occurs predominantly in the later cycles of sleep, so reducing total sleep time disproportionately reduces REM duration.

Question 3

During which stage of sleep is the glymphatic system most active, and what is its primary function?

Accepted Answer

The glymphatic system is most active during deep sleep, clearing metabolic waste from the brain.

Question 4

Which of the following is an example of a phasic receptor?

Accepted Answer

Meissner's corpuscle, which rapidly adapts to touch stimuli.

Question 5

What is the process of transduction in sensory physiology?

Accepted Answer

Conversion of a stimulus into an electrical signal by a sensory receptor.

Question 6

Which aspect of sensory perception allows the CNS to determine the intensity of a stimulus?

Accepted Answer

The frequency of action potentials generated by sensory neurons.

Question 7

Lateral inhibition in sensory pathways enhances which aspect of perception?

Accepted Answer

Contrast and localization of the stimulus.

Question 8

A patient experiences pain in the left arm during a heart attack. This is an example of:

Accepted Answer

Referred pain.

Question 9

Which neurotransmitter is most commonly associated with nociception?

Accepted Answer

Substance P

Question 10

What is the primary difference between pain threshold and pain tolerance?

Accepted Answer

Pain threshold is the minimum stimulus intensity required to perceive pain; pain tolerance is the maximum intensity of pain a person can endure.

Question 11

Which of the following best explains why peripheral nerves can regenerate but CNS neurons cannot?

Accepted Answer

Schwann cells in the PNS form regeneration tubes, while oligodendrocytes in the CNS do not support regeneration and release inhibitory factors.

Question 12

Which sequence correctly describes the steps in peripheral nerve regeneration?

Accepted Answer

Axon fragmentation, macrophage cleanup, Schwann cell proliferation, regeneration tube formation, axon regrowth.

Question 13

Which of the following is NOT a component of a simple spinal reflex arc, such as the patellar tendon reflex?

Accepted Answer

Cerebral cortex

Question 14

At the neuromuscular junction (NMJ), which event directly triggers muscle contraction?

Accepted Answer

Acetylcholine binds to receptors on the muscle cell membrane, leading to depolarization and action potential generation.

Question 15

Which of the following best describes the function of varicosities in autonomic neurons?

Accepted Answer

Varicosities release neurotransmitters along the length of the axon, affecting a broad area of target tissue.

Question 16

Which equation best represents the relationship between stimulus intensity and action potential frequency in sensory neurons?

Accepted Answer

$$f = k 	imes I$$

Question 17

A patient reports pain in a limb that has been amputated. This phenomenon is known as:

Accepted Answer

Phantom pain

Question 18

Which of the following is a tonic receptor?

Accepted Answer

Muscle spindle, which continuously monitors muscle stretch.

Question 19

Which classification of sensory receptors is responsible for detecting changes in temperature?

Accepted Answer

Thermoreceptors

Question 20

Sensory tracts in the spinal cord are located in which region?

Accepted Answer

Dorsal horn or root

Bio 221 Human Physiology Quiz #3 Study Guide – Step-by-Step Guidance

Study Guide - Practice Questions