Autonomic Nervous System (Lec 22)

Question 1

Structural difference between somatic nervous system and autonomic nervous system

Answer 1

SNS

• conscious control of motor output
• 1 neuron peripheral motor pathway
• perception of sensory input: yes

ANS

• independent - no concious
• 2 neuron peripheral motor pathway
• perception of sensory input: no

Question 2

Functional difference between somatic nervous system and autonomic nervous system

Answer 2

SNS
Sensory input: external environment
Motor output: skeletal muscle

ANS
Sensory input: internal environment
Motor output: internal organs

Question 3

Anatomy of Autonomic nerve pathways

Answer 3

Consists of 2 neurons
- preganglionic (myelinated) and postganglionic (unmyelinated) meet in synapse in autonomic ganglion
-

Question 4

Physiological effects related to the sympathetic divisions of ANS

Answer 4

Fight or flight response to danger to mobilize body for action

• increases heart rate
• increases respiratory rate
• releases glucose
• dilates pupils
• reduces other processes to focus energy on danger (digestion)

Question 5

Physiological effects related to the parasympathetic divisions of ANS

Answer 5

Utilized in ordinary situations (rest & digest)

• slows heart rate
• decreasing respiration if rate
• stimulates digestion
• stores glucose

Question 6

ANS divisions

Answer 6

• sympathetic

- parasympathetic

Question 7

What is the output of the sympathetic nervous system called

Answer 7

Thoracolumbar outflow

Question 8

Sympathetic nervous system: The postganglionic neurons originate in peripheral ganglia in 2 locations

Answer 8

• Sympathetic chain ganglia
  
  • lie along vertebral column
  • output - viscera above diaphragm
• Prevertebral ganglia
  
  • lie within abdominal cavity
  • output - viscera below diaphragm

Question 9

Pathways for sympathetic postganglionic neurons after sympathetic chain (trunk)

Answer 9

• postganglionic - spinal nerves - skin of body
• postganglionic - parietal nerves - skin of face & viscera of head
• postganglionic - sympathetic nerves - viscera of thoracic cavity
• preganglionic go through sympathetic trunk (chain) - relay to postganglionic in prevertebral ganglia - viscera of abdominal/pelvic cavity

Question 10

Sympathetic nervous system: postganglionic neurons that originate in the __________ transmit signals to viscera above the diaphragm

Answer 10

sympathetic trunk ganglia

Question 11

Sympathetic nervous system: postganglionic neurons that originate in the __________ transmit signals to viscera below the diaphragm

Answer 11

Prevertebral ganglia

Question 12

What is the output of parasympathetic nervous system

Answer 12

Craniosacral outflow

Question 13

Postganglionic neurons of parasympathetic nervous system originate in ________

Answer 13

Terminal ganglia

Located within/close to visceral organs

Question 14

Cranial nerves that have autonomic motor functions (parasympathetic axons contained within)

Answer 14

CN III, CN VII, CN IX, CN X

Question 15

Sympathetic NS: Preganglionic neurons arise from _________ spinal cord (exit spinal cord via spinal nerves)

Answer 15

T1-L2

Question 16

Parasympathetic NS: Preganglionic neurons arise from _______ and ______ of spinal cord

Answer 16

Brain stem (for viscera above pelvic cavity)
S2 - S4 (within pelvic cavity)

(exit brainstem via cranial nerve, exit spinal cord via spinal nerves)

Question 17

What regulates the balance between the physiological effects of the competing parasympathetic and sympathetic nervous system

Answer 17

Hypothalamus