Ch 48 (test 1)

Question 1

where are free nerve endings found

Answer 1

skin and deep tissue and viscera

Question 2

can free nerve endings adapt

Answer 2

very little

Question 3

what chemicals cause pain stimuli

Answer 3

enodgenous–bradykinin, K ions, histamine, proteolytic enz.

Question 4

what kind of sensory fibers are pain receptors

Answer 4

fast pain–A delta

slow pain–C

Question 5

what layer is the lamina marginalis found in

Answer 5

layer 1

Question 6

what layer is the substangia gelatinosa found

Answer 6

layer 1 and 2

Question 7

where in the cord are cell bodies located

Answer 7

gray matter

Question 8

where in the cord are myelinated axons located

Answer 8

white matter

Question 9

what pathway does fast pain take in the cord

Answer 9

neospinothalamic pathway

Question 10

describe the neospinothalamic pathway

Answer 10

• synapse in lamina 1
• 2nd order decussates in cord and up through anterolateral column to thalamus
• synapse in thalamus
• 3rd order to SSA1

Question 11

what pathway does slow pain take in the cord

Answer 11

paleospinothalamic pathway

Question 12

describe the paleospinothalamic pathway

Answer 12

• 1st order neurons synapse in lamina 1, 2 and 3 and/or 5
• 2nd order decussates in cord
• travels up anterolateral column to reticular formation/thalamus (brain stem)

Question 13

pain suppression of the brain and cord are done by what system

Answer 13

analgesia system

Question 14

describe how the analgesia system works

Answer 14

• AP generated in periventricular nuclei and periaqueductal gray
• AP sent to nucleus raphe magnus
• AP sent down cord to the inhibitory neuron, enkephalin
• inhibits excitatory pain receptor neuron

Question 15

pain in part of the body that is distant to the area where the pain occurs

Answer 15

referred pain

Question 16

why is visceral pain felt on the surface of the skin

Answer 16

synapse on same 2nd order neuron

Question 17

3 causes of visceral pain

Answer 17

Ischemia
cramps
overdistention

Question 18

what is ischemia

Answer 18

lack of oxygen, releases endogenous chemicals

Question 19

what are cramps

Answer 19

smooth muscle contractions

Question 20

what is overdistention

Answer 20

stretchingo fvisceral tissure (ex–full bladder)

Question 21

why is visceral pain difficult to localize

Answer 21

1-no input from visual cortex

2-transmitted by 2 pathways

Question 22

what 2 pathways is visceral pain transmitted by

Answer 22

true visceral–referred pain

parietal pathway–lacalized directly at area via from peritoneum

Question 23

what are 3 main causes of headaches

Answer 23

1-tuggin on venous sinuses
2-stretching the dura mater
3-damage to blood vessels in meninges

Question 24

What pathways do the somatic senses (mechanoreceptive, thermoreceptive, and pain) use

Answer 24

mechano–DC-ML, slight anterolateral
thermo–antero
pain–antero

Question 25

what kind of nerve endings do warmth receptors use

Answer 25

free nerve endings (type C)

Question 26

what kind of nerve endings do cold receptors use

Answer 26

free nerve endings (type C)
unidentified receptor (type A delta)

Question 27

what kind of nerve endings do heat/cold pain receptors use

Answer 27

free nerve endings (type C)

Question 28

do thermoreceptors adapt quickly

Answer 28

yes–to change in temp and constant temp