Interaction and Control of the Autonomic Nervous System

Question 1

Fibers that release Ach. Include all ANS preganglionic axons and all parasympathetic postganglionic axons at synapses with their effectors.

Answer 1

Cholinergic Fibers

Question 2

Fibers that release norepinephrine. Include majority of sympathetic postganglionic fibers.

Answer 2

Adrenergic Fibers

Question 3

Ach receptors that also bind to nicotine. Found on all postganglionic neurons, the hormone-producing cells of the adrenal medulla, and the sarcolemma of skeletal muscle cells at neuromuscular junctions. Ach binding always causes a stimulatory effect.

Answer 3

Nicotinic Receptors

Question 4

Ach receptors that also bind to muscarine, a mushroom poison. Found on effector cells stimulated by postganglionic cholinergic fibers (all parasympathetic target organs and a few sympathetic targets.) Ach binding can be stimulatory or inhibitory.

Answer 4

Muscarinic Receptors

Question 5

Receptor for NE. Effects are generally stimulatory.

Answer 5

Alpha Receptors

Question 6

Receptor for NE. Effects are generally inhibitory.

Answer 6

Beta Receptors

Question 7

Occurs due to blood vessels being kept in a continual state of partial constriction.

Answer 7

Sympathetic Tone

Question 8

Fibers that increase rate of fire to cause blood vessels to constrict and raise blood pressure or decrease rate of fire to dilate and reduce blood pressure.

Answer 8

Vasomotor Fibers

Question 9

Slows the heartrate and dictates the normal activity levels of the digestive and urinary tracts.

Answer 9

Parasympathetic Tone

Question 10

What functions are only controlled by the sympathetic division?

Answer 10

The adrenal medulla, sweat glands, arrector pili muscles of the skin, the kidneys (release renin), and most blood vessels (alters blood pressure and body temp).

Question 11

What are the three levels of control of the ANS.

Answer 11

The hypothalamus is the main integration center.
The Brain Stem and the Spinal Cord play a role in autonomic reflexes.
There is some degree of voluntary cortical control over the ANS.