Question 1

Which of the following best describes the difference in the anatomical arrangement of neurons between the sympathetic and parasympathetic divisions of the autonomic nervous system (ANS)?

Accepted Answer

Sympathetic preganglionic neurons are short and postganglionic neurons are long; parasympathetic preganglionic neurons are long and postganglionic neurons are short.

Question 2

A patient is prescribed a beta-1 adrenergic antagonist (beta blocker) to manage hypertension. Which of the following physiological effects would you expect as a result of this medication?

Accepted Answer

Decreased heart rate and decreased force of cardiac contraction

Question 3

Which neurotransmitter is released by all preganglionic neurons of both the sympathetic and parasympathetic divisions of the ANS?

Accepted Answer

Acetylcholine

Question 4

A person stands up quickly and experiences a sudden drop in blood pressure (orthostatic hypotension). Which division of the ANS is primarily responsible for correcting this drop, and through which mechanism?

Accepted Answer

Sympathetic division; increasing heart rate and causing vasoconstriction via norepinephrine release

Question 5

Which receptor type is found on the smooth muscle cells of blood vessels supplying the skin and is responsible for vasoconstriction when activated by norepinephrine?

Accepted Answer

Alpha-1 adrenergic receptor

Question 6

A drug that acts as a muscarinic antagonist is administered to a patient. Which of the following effects would most likely be observed?

Accepted Answer

Dry mouth and decreased gastrointestinal secretions

Question 7

Which of the following best explains why the effects of the adrenal medulla last longer than those of direct sympathetic postganglionic neuron stimulation?

Accepted Answer

The adrenal medulla releases norepinephrine and epinephrine into the bloodstream, allowing them to act as hormones with longer-lasting effects.

Question 8

Which of the following is a direct effect of sympathetic nervous system activation on the digestive system?

Accepted Answer

Constriction of blood vessels serving the digestive organs, leading to decreased digestion

Question 9

A patient with asthma is prescribed a beta-2 adrenergic agonist. What is the expected effect of this medication on the respiratory system?

Accepted Answer

Bronchodilation due to relaxation of airway smooth muscle

Question 10

Which cranial nerve carries the majority of parasympathetic fibers to the thoracic and abdominal viscera?

Accepted Answer

Vagus nerve (X)

Question 11

Which of the following best describes the concept of dual innervation in the autonomic nervous system?

Accepted Answer

Most organs receive input from both sympathetic and parasympathetic neurons, allowing for precise regulation of organ function.

Question 12

Which of the following is a direct effect of parasympathetic nervous system activation on the urinary system?

Accepted Answer

Relaxation of urinary sphincters, promoting urination

Question 13

A patient is given an alpha-1 adrenergic blocker to treat hypertension. Which of the following is the most likely mechanism by which this drug lowers blood pressure?

Accepted Answer

It causes vasodilation by preventing norepinephrine from binding to alpha-1 receptors on vascular smooth muscle.

Question 14

Which of the following best explains why the parasympathetic nervous system has little effect on most blood vessels?

Accepted Answer

Most blood vessels lack parasympathetic innervation.

Question 15

Which of the following is a correct sequence of events in a visceral reflex arc mediated by the ANS?

Accepted Answer

Sensory signal → CNS integration → efferent motor neuron → autonomic ganglion → target organ

Question 16

Which of the following best describes the effect of norepinephrine binding to beta-3 adrenergic receptors on adipocytes during sympathetic activation?

Accepted Answer

It stimulates the breakdown of lipids, increasing free fatty acids in the blood.

Question 17

Which of the following is a direct effect of parasympathetic stimulation via the oculomotor nerve (III)?

Accepted Answer

Constriction of the pupil

Question 18

A patient is experiencing 'white as a sheet' appearance during a stressful event. Which physiological mechanism best explains this phenomenon?

Accepted Answer

Vasoconstriction of blood vessels in the skin via alpha-1 adrenergic receptor activation

Question 19

Which of the following statements about autonomic tone is correct?

Accepted Answer

Autonomic tone refers to the constant activity of both sympathetic and parasympathetic divisions, allowing for fine-tuned regulation of organ systems.

Chapter 14: The Autonomic Nervous System and Homeostasis - Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards