Chapter 16: The Autonomic Nervous System

Question 1

Causes contraction of skeletal muscle
Controls voluntary responses

Answer 1

Somatic Nervous System

Question 2

Controls cardiac and smooth muscle and glands
Controls involuntary responses
Helps maintain homeostasis in the body

Answer 2

Autonomic Nervous System

Question 3

Associated with “fight-or-flight” responses

Answer 3

Sympathetic Nervous System

Question 4

Associated with “rest and digest” responses

Answer 4

Parasympathetic Nervous System

Question 5

Responds to a threat to our homeostasis (stress) or enables survival
Increases oxygen delivered to skeletal muscle
Increases sweating
Blood is shifted away from the digestive system and toward skeletal muscle
Pupils dilate
Brain becomes alert

Answer 5

Sympathetic Division of the Autonomic Nervous System

Question 6

Preganglionic cell bodies in thoracic and lumbar regions of spinal cord

Answer 6

thoracolumbar system

Question 7

Preganglionic cell bodies in thoracic and lumbar regions of spinal cord
23 ganglia located next to vertebral column
Some preganglionic neurons synapse outside of sympathetic chain

Answer 7

Sympathetic Pathways

Question 8

project through white rami communicantes and can synapse:
At the ganglion at the same level
At a more superior or inferior ganglion
At prevertebral ganglia or the adrenal medulla

Answer 8

Short preganglionic axons

Question 9

project to target effector through gray rami communicantes

Answer 9

Long postganglionic axons

Question 10

Includes the celiac ganglion, superior mesenteric ganglion, and inferior mesenteric ganglion

Answer 10

Collateral Ganglia

Question 11

Located anterior to vertebral column
Also known as prevertebral ganglia

Answer 11

Collateral Ganglia

Question 12

Help regulate activities of abdominal organs
Considered part of enteric nervous system
Receive input from splanchnic nerves and central sympathetic neurons

Answer 12

Collateral Ganglia

Question 13

is in lateral horn of the thoracic or lumbar region of the spinal cord

Answer 13

Cell body of the preganglionic neuron

Question 14

synapses with postganglionic neuron close to spinal cord

Answer 14

Preganglionic axon

Question 15

synapses within target organ

Answer 15

Long postganglionic axon

Question 16

Used at the synapse of the sympathetic preganglionic and postganglionic neurons

Answer 16

Acetylcholine (ACh)

Question 17

Released by postganglionic neurons onto target cells

Answer 17

Norepinephrine

Question 18

Activation of the sympathetic NS can cause hormone release in the adrenal medulla

Answer 18

Epinephrine (adrenaline) and norepinephrine (noradrenaline)

Question 19

Preganglionic axons terminate in adrenal medulla

Answer 19

No ganglion involved

Question 20

Active when body is not stressed or under a threat
Controls “rest and digest” activities
Salivation
Lacrimation (the flow of tears)
Urination
Digestion
Defecation
Sexual arousal

Answer 20

Parasympathetic Division of the Autonomic Nervous System

Question 21

Cell bodies of preganglionic neurons located in brain stem and sacral spinal cord

Answer 21

craniosacral system

Question 22

project to ciliary ganglion; postganglionic neurons then control iris

Answer 22

Preganglionic axons in oculomotor nerve (CN III)

Question 23

project to pterygopalatine and submandibular ganglia to control production of saliva, mucus, and tears
Innervates two of the three salivary gland pairs

Answer 23

Preganglionic axons in facial nerve (CN VII)

Question 24

project to otic nucleus to control saliva production
Innervates only one pair of salivary glands

Answer 24

Preganglionic axons of glossopharyngeal nerve (CN IX)

Question 25

to innervate organs in thoracic, abdominal, and pelvic cavities Preganglionic axons mix with sympathetic postganglionic axons in plexuses

Answer 25

Preganglionic axons project through vagus nerves (CN X)

Question 26

Travel through hypogastric plexus and synapse in terminal or intramural ganglia Postganglionic axons project into pelvic cavity

Answer 26

Preganglionic axons from sacral region form pelvic splanchnic nerves

Question 27

Acetylcholine (ACh) is neurotransmitter released

Answer 27

Cholinergic synapses

Question 28

Norepinephrine is neurotransmitter released

Answer 28

Adrenergic synapses

Question 29

Endogenous ligand—acetylcholine Exogenous ligand—nicotine Chemically-gated ion channel

Answer 29

Nicotinic receptors

Question 30

Endogenous ligand—acetylcholine Exogenous ligand—muscarine Trigger changes in cell without allowing ions to pass through membrane

Answer 30

Muscarinic receptors

Question 31

—located in skin, GI and pelvic organs, and blood vessels Cause contraction of smooth muscle

Answer 31

α1

Question 32

—found in pancreas, platelets, brain, and spinal cord Inhibit insulin release Promote blood clotting

Answer 32

α2

Question 33

—found in heart and kidney Increase heart rate, force of contraction, and secretion of renin

Answer 33

β1

Question 34

—found in blood vessels, lungs, uterus, stomach, and small intestines Cause relaxation of smooth muscle

Answer 34

β2

Question 35

—found in adipose tissue Stimulate breakdown of lipids

Answer 35

β3

Question 36

Help maintain internal homeostasis Blood pressure Heart rate Airway diameter Digestive activity

Answer 36

Autonomic Reflexes

Question 37

single neuron, Sensory info comes from somatic and special senses and viscera

Answer 37

Afferent branch

Question 38

two neuron, Preganglionic neuron synapses with postganglionic neuron in a ganglion

Answer 38

Efferent branch

Question 39

regulates heart rate and strength of contractility

Answer 39

Cardiac plexus

Question 40

regulates size of airways in lungs

Answer 40

Pulmonary plexus

Question 41

regulates movement of food through esophagus

Answer 41

Esophageal plexus

Question 42

regulates abdominal organs and pelvic tissues

Answer 42

Abdominal aortic plexus

Question 43

Both divisions of the autonomic nervous system innervate most organs

Answer 43

dual innervation

Question 44

effects of parasympathetic nervous system are seen

Answer 44

Parasympathetic dominance

Question 45

effects of sympathetic nervous system are seen Opposite of parasympathetic effects

Answer 45

Sympathetic dominance

Question 46

Balance between parasympathetic and sympathetic dominance when an organ is at rest

Answer 46

Autonomic Tone

Question 47

dominates the heart at rest Lowers heart rate to normal range

Answer 47

Parasympathetic tone

Question 48

dominates blood vessels at rest Adjusts constriction of vessels to maintain blood pressure

Answer 48

Sympathetic tone

Question 49

Autonomic nervous system helps body respond to stress Aim is to increase nutrients in blood and deliver more blood to head and muscles

Answer 49

Stress