Skin and temperature control Flashcards
firing rate of hot and cold receptors
hot- increase firing rate to heat
cold decrease to cold
where are peripheral chemoreceptors found x2
Located in the skin, especially in face,
scrotum
where are Central thermoreceptors found x3
spinal cord
abdominal organs
hypothalamus
what do peripheral chemoreceptors sense
what do central chemoreceptors sense
peripheral- change in environmental temperature
central- change in core body temperature
what do infants do in the cold
what do they use for it
*Non-shivering thermogenesis
*brown adipose tissue
how is heat loss reduced
*Vasomotor control:
-Sympathetic arteriolar constriction reduces delivery of blood to the skin
*Behavioural responses
- Adding clothing, moving to warmer environment, reducing surface area
what temperature does hypothermia occur at
35
fancy medical way to rewarm someone
extracorporeal circulation- taking blood out, rewarming it and putting it back in
what nerves cause sweating
Sympathetic cholinergic fibres
heat vs cold on peripheral arterioles
heat- dilate
cold- constrict
what causes heat exhaustion vs heat stroke
exhaustion- disturbance of the body’s fluid/salt balance due to excessive sweating
stroke- Body temperature raised above 40 ºC and temperature control mechanisms fail
symptoms of heat exhaustion vs stroke
exhaustion- headache, confusion, nausea, profuse sweating, clammy skin, tachycardia, hypotension, weak pulse, fainting and collapse
stroke- hot dry skin (sweating stops) and circulatory collapse
what causes fever
endogenous pyrogens (IL-1, IL-6)
what actually brings the temp up in a fever
Endogenous pyrogens shift the set point for temp
Caused by local production of prostaglandins by cyclo-oxygenase in the hypothalamus
