Chapter 22: Autonomic Nervous System (by Liz)

Question 1

The major function of ANS

Answer 1

• Regulate heartbeat, smooth muscle contraction, glandular secretions, and metabolic functions to maintain homeostatic balance and react to threats to that balance
• not skeletal muscle

Question 2

What are the two components of the ANS

Answer 2

• Afferent (sensory)

- Efferent (motor)

Question 3

All autonomic neurons function in:

Answer 3

Reflex arcs

Question 4

Reflex arcs:

Answer 4

Are called autonomic reflexes or visceral reflexes

Question 5

What are the three paths a preganglionic fiber may take once inside the sympathetic chain ganglion?

Answer 5

• Synapse with sympathetic postganglionic neuron
• Send ascending or descending branches through the sympathetic trunk to synapse with postganglionic neurons in other chain ganglion
• Pass through one or more chain ganglia without synapsing

Question 6

Where do parasympathetic preganglionic neurons have cell bodies?

Answer 6

In nuclei in the brainstem or lateral gray columns of the sacral cord

-They extend a considerable distance before synapsing with postganglionic neurons

Question 7

Adrenergic fibers

Answer 7

Release norepinephrine

Question 8

Cholinergic fibers release

Answer 8

Acetylcholine

Question 9

Epinephrine also stimulate

Answer 9

Adrenergic receptors

Question 10

Tonically active

Answer 10

• Sympathetic and parasympathetic divisions are tonically active
• can act maintain the normal function owning of doubly innervated autonomic effectors

Question 11

Know this-It was highlighted in RED!

Answer 11

• Dually innervated effectors continually receive both sympathetic and parasympathetic impulses, and the summation of the two determines the controlling effect.
• The autonomic nervous system does not function autonomously, as its name suggests; it is continually influenced by impulses from the so-called autonomic centers.
• These are clusters of neurons located at various levels in the brain whose axons conduct impulses directly or indirectly to autonomic preganglionic neurons.
• The major function of the sympathetic division is to serve as an emergency system (the “fight-or-flight” reaction).
• See Table 22-4 (p. 514) for more details on autonomic functions.
• Acetylcholine stimulates digestive gland secretion.
• It also increases peristalsis by stimulating the smooth muscle of the digestive tract.