Thermoregulation

Question 1

warm sensitive thermoreceptors

Answer 1

TRP - V1 to V4
sensitive over different ranges
activated by vanilloid (capsaicin, hot peppers)

Question 2

cold sensitive thermoreceptors

Answer 2

TRPM8 and TRPA2
sensitive over different ranges
activated by menthol

Question 3

activation of warm or cold thermoreceptors

Answer 3

opens as temperature increases or decreases

allows Na or Ca influx

Question 4

anterior hypothalamus thermoregulatory system

Answer 4

responds to heat

heat LOSS behaviors

Question 5

posterior hypothalamus thermoregulatory system

Answer 5

responds to cooling

heat PRODUCTION behavior

Question 6

cutaneous thermoreceptors

Answer 6

bimodal (temperature and touch sensitive)
warm or cold sensitive
10x as many COLD sensitive
tell about environmental conditions

Question 7

visceral thermoreceptors

Answer 7

sense core temperature
threat to maintenance of body temp
food ingested may change body T

Question 8

central thermoreceptors

Answer 8

location: PRE OPTIC and SUPEROPTIC regions of hypothalamus
3x as many WARM sensitive
relay info to other areas of hypothalamus

Question 9

hypothalamus - thermoregulation

Answer 9

integration of afferent
determination of set point
compare core temp to set point and if its different generates a response
respond to environment

Question 10

heat production

Answer 10

ANS - sympathetic
Hormonal - thyroxin, epi/norepi
heat production - mm activity, non-shivering thermogenesis

Question 11

heat production - muscular activity

Answer 11

shivering - DORSOMEDIAL posterior hypothalamus, increase motorneuron excitation
increase voluntary activity - CORTEX, jumping or running

Question 12

heat production - non-shivering

Answer 12

hormonal - thyroxin increases metabolic rate, epi
increase food intake - increase metabolism
brown adipose tissue

Question 13

brown adipose tissue

Answer 13

low efficiency hydrolysis of ATP
sympathetic inn
strong in infants

Question 14

heat loss - evaporative

Answer 14

insensible - respiratory

sweating - controlled

Question 15

heat loss - convection

Answer 15

movement of molecules away from contact

Question 16

heat loss - conduction

Answer 16

transfer of heat b/w objects in physical contact with one another

Question 17

heat loss - radiation

Answer 17

infrared radiation transferring heat b/w 2 objects not in physical contact

Question 18

response to increased core temperature

Answer 18

decrease in heat production - apathy/inertia, anorexia

increase in heat loss - blood to skin, EHL, insensible heat loss

Question 19

sweat glands

Answer 19

inn - sympathetic cholinergic (ACH) binding to muscarinic R
lots of blood vessels
coiled region by vessels
duct leading to skin

Question 20

primary sweat secretion

Answer 20

high in water and sodium

water and sodium are reabsorbed (taken back into the blood) in the duct of the sweat gland

Question 21

low flow sweat rate

Answer 21

CONCENTRATED
little water
high sodium

Question 22

high flow sweat rate

Answer 22

DILUTED
lots of water
little sodium

Question 23

response to decrease in core temperature

Answer 23

increase heat production - shivering, non - shivering thermogenesis
decrease heat loss - blood away from skin, decrease EHL

Question 24

Fever

Answer 24

controlled increase in body temperature

SET POINT INCREASES body temperature is only doing what hypothalamus directs it to do

Question 25

making a fever step 1

Answer 25

the bug stimulates secretion of endotoxins immune cells release cytokines both stimulate production of PGE2 this increases the set point so it is greater than body temperature

Question 26

making a fever step 2

Answer 26

increase heat production - shivering, non - shivering thermogenesis decrease heat loss - blood away from skin, decrease EHL

Question 27

making a fever step 3

Answer 27

body temperature will reach set point | comfort in a relative sense

Question 28

making a fever step 4

Answer 28

the bug is removed and the immune system is no long activated set point will return to normal so now body temperature is more than set point

Question 29

making a fever step 5

Answer 29

decrease in heat production - apathy/inertia, anorexia | increase in heat loss - blood to skin, EHL, insensible heat loss

Question 30

hyper and hypothermia

Answer 30

uncontrolled changes in body temperature implications - SET POINT remains NORMAL, environmental stresses exceed body's ability to regulate temp, at extremes hypothalamic regulation may be lost