PNS PT 1

Question 1

what does the peripheral nervous system include

Answer 1

all neural structures outside of the brain and spinal cord, so sensory receptors, peripheral nerves + ganglia, efferent motor endings

Question 2

what do the various components of the PNS do

Answer 2

link our CNS to other parts of our body and our surroundings

Question 3

what are nerves

Answer 3

bundle of axons of various neurons

Question 4

do nerves have artery + blood supply

Answer 4

yes

Question 5

describe the two arms of the autonomic nervous system

Answer 5

sympathetic division, which is fight or flight
parasympathetic division, which is rest and digest

Question 6

describe the parasympathetic division of the ANS

Answer 6

rest and digest; keeps body energy use as los as possible, even while carrying out maintenance activities, like digestion, diuresis, defecation; bp, heart rate and respiratory rates are low and GI tract activity is high

Question 7

what innervates the PNS

Answer 7

vagus nerves

Question 8

describe vagus nerves + other PNS nerves

Answer 8

account for ~90% of all preganglionic parasympathetic fibers in the body; serve all thoracic and abdominal viscera

Question 9

where do PNS pregang fibers arise from

Answer 9

medulla and synapse in terminal ganglia in walls of target organs

Question 10

describe the sympathetic division of the ANS

Answer 10

fight or flight; mobilizes body during activity; activated by exercise, excitement, emergency, embarrassment

Question 11

what happens when SNS is on

Answer 11

increased heart rate, dry mouth; blood to skeletal muscles and heart; dilates bronchioles, causes liver to release glucose

Question 12

does the SNS or PNS act on adrenal medulla

Answer 12

only the sympathetic nervous system

Question 13

where do you find muscainic receptors

Answer 13

only on organs stimulated by the PNS

Question 14

where does the somatic nervous system release Ach

Answer 14

at neuromuscular junctions

Question 15

what neurotransmitter does the somatic nervous system release

Answer 15

ach

Question 16

what neurotransmitter do pre and post ganglia release in pns

Answer 16

ach

Question 17

describe the two pre/post gang SNS pathways

Answer 17

first one: lightly myelinated pre gang release Ach at nicotinic receptor and then nonmyelinated post release NE at muscinaric receptor
second one: lightly myelinated pre gang release Ach at adrenal medulla, which releases NE and E into blood vessel

Question 18

describe parasympathetic nervous system pre and post gang pathways

Answer 18

light myelinated pre release Ach at niotonic receptors and nonmyelinated post release Ach at muscarnic receptors

Question 19

what are the effector organs of the autonomic nervous system (so parasymp and sympathetic)?

Answer 19

smooth muscle, glands, cardiac muscle

Question 20

how does the PNS act on heart and digestive tract?

Answer 20

speeds up heart, slows down digestion

Question 21

describe effects of somatic nervous system vs autonomic (sympathetic and parasymp)

Answer 21

somatic nervous system is always stimulatory, but autonomic is sometimes stimulatory and sometimes inhibitory, depending on neurotransmitter and receptor on effector organs

Question 22

what are sensory receptors

Answer 22

specialized to respond to changes (stimuli) in their environment

Question 23

how are sensory receptors classified

Answer 23

type of stimulus they detect, body location, structural complexity

Question 24

what are mechanoreceptors

Answer 24

sense touch, pressure, tension, movement

Question 25

where are mechanoreceptors located

Answer 25

skin, ears, muscles

Question 26

what are thermoreceptors

Answer 26

respond to changes in temperature

Question 27

where are thermoreceptors located

Answer 27

skin, hypothalamus

Question 28

what are photoreceptors + where are they located

Answer 28

sense changes in light and located in the eye

Question 29

what are chemoreceptors and where are they located

Answer 29

sense chemical stimuli and located in the tongue and nose

Question 30

what are nocicreceptors and where are they located

Answer 30

sense tissue damage/pain; located anywhere that can sense noxious stimuli

Question 31

what are extereoreceptors

Answer 31

located outside body + near body surface; sense touch, pressure, pain on skin, special sense

Question 32

what are interoreceptors

Answer 32

located in the body (internal viscera, blood vessels); tissue stretch, body temp, chemical changes

Question 33

what are proprioreceptors

Answer 33

in body, advising brain of external body movement; located in skeletal muscles, tendons, joints, ligaments