Ch 15 Autonomic Nervous System

Question 1

function of ans

Answer 1

unconscious bodily function
occasionally require instantaneous diversion of energy

Question 2

how does ans work and are its effectors

Answer 2

innervates smooth, cardiac muscle, and glands (effectors)
operate via unconscious control

Question 3

SNS vs ANS axons

Answer 3

sns is heavily myelinated and axons extend from cns
ans axons are part of two-neuron chaing (preganglionic is lightly myelinated, postgangionic is not)

Question 4

what nt is release by sns

Answer 4

acetylcholine

Question 5

what nt is released by ans

Answer 5

preganglionic fibers release ACh, postganglionic release NE or ACh

Question 6

sns excitatory or inhibitroy

Answer 6

excitatory

Question 7

ans excitatory or inhibitory

Answer 7

both

Question 8

division of ans

Answer 8

sympathetic and parasympathetic

Question 9

role of sympathetic

Answer 9

mobilized body during extreme situations
e activities - exercise, excitement, emergency, embarassment

Question 10

role of parasympathetic

Answer 10

performs maintenance activities and conserved body energy
d activities digestion, defecation, diuresis

Question 11

when sympathetic is in control

Answer 11

HR increases, deep breathing, tachypnea, blood flow to organs reduced and muscles increased, skin cold and sweaty, pupils dilate

Question 12

when parasympathetic is in control

Answer 12

BP HR RR low, GI tract activity high, skin warm (blood in skin), pupils constricted, diuresis

Question 13

length of preganglionic nerves and postganglionic nerves

Answer 13

sympathetic - pre short post long
parasympathetic - pre long post short

Question 14

where do sympathetic neurons exit spinal cord

Answer 14

T1-L2

Question 15

where do parasympathetic neurons exit spinal cord

Answer 15

cranial 3, 7, 9, 10 and S2-4

Question 16

ans tone

Answer 16

a system actin g on its own, increased tone means increased activity

Question 17

sympathetic tone

Answer 17

controls BP
tone goes up, BP rises as blood vessels constrict
tone goes dow, BP lowers as blood vessels dilate

Question 18

parasympathetic tone and whats important to note

Answer 18

control HR and levels of digestive and urinary system
tone goes up, HR slows
tone goes down, HR rises
sympathetic can override this at any time

Question 19

cholinergic fibers

Answer 19

ACh relasing
all preganglionic axons
parasympathetic postganglionic axons
may bind to nicotinic or muscarinic receptors

Question 20

adrenergic fibers

Answer 20

NE releasing fibers
sympathetic postganglionic fibers
may bind to α or β receptors

Question 21

nicotinic receptors

Answer 21

always excitatory
found on motor end plates

Question 22

muscarinic receptors

Answer 22

inhibitory or excitatory
slows heart rate and strength of muscle contractions
increases digestive activity
constriction of iris

Question 23

beta blockers

Answer 23

attach mainly to β adrenergic receptors and lower HR and prevent arrythmias