Chapter 15 - The Autonomic Nervous System

Question 1

Autonomic Nervous Systems

Answer 1

System of MOTOR neurons that innervate smooth muscle, cardiac muscle, and glands
Regulates visceral functions (heart rate, blood pressure, digestion, urination)
General visceral motor division
MOST peripheral nerves serve the somatic system: all mixed cranial nerves, all spinal nerves
SOME peripheral nerves serve the autonomic and somatic: some cranial nerves, thoracic, lumbar, and sacral spinal nerves. NOT cervical

Question 2

Adrenal Medulla

Answer 2

Adrenal gland is located on superior side of kidney
-cortex: outer portion
-medulla: inner portion
Controlled by sympathetic nervous system
secretion: epinephrine and NE
Target: all sypathetic target organs
Effects: reinforces sympathetic mass activation, hormonal effect lasts longer
inc. HR, dilate coronary vessels, inc mental alertness, inc resp. rate, inc metabolic rate

Question 3

General visceral neurons

Answer 3

stretch, temp, chemical, irritation

most are free nerve endings

Question 4

referred pain

Answer 4

difficulty pinpointing signals
people often perceive that the pain is coming from somatic areas like the skin or outer body (ex. heart attack and arm pain)

Question 5

Control of ANS

Answer 5

Brain stem and spinal cord
hypothalamus (main integration center of ANS)
amygdala
cerebral cortex

Question 6

Autonomic dysreflexia

Answer 6

mass reflex reaction
uncontrolled activation of ANS motor neurons
affects people with spinal cord injuries about T6 level
when cord injury first happens there are no reflexes, but they return later and are exaggerated due to lack of inhibitory input from brain
Initial trigger causes mass activity of reflexes - body spasms, colon and bladder empty, sweating, high BP
Exact mechanism unknown