CHAPTER 12 Flashcards
where is temperature controlled
thermoregulatory centre
where is the thermoregulatory centre
the hypothalamus brain
how does the thermoregulatory centre detect changes
receptors test temperature of blood in brain receptors in skin
how does the body cool down
sweat vasodilation
what is vasodilation
the blood vessels near the skin dilate so more blood is exposed to the cool air and cools down
how does sweat cold you down
it evaporates from the skin takin heat with it
how does the body warm up
vasoconstriction
shiver
hairs stand on end
how does hair standing on end warm you up
it catches and traps an insulating layer of air
how does shivering warm you up
the movement of skeletal system means for respiration (an exothermic process)this heats up the body
what is vasoconstriction
blood vessels constrict near the skin so less blood is available to the cold air
why should the body not get too hot
dentures enzymes
what are the two main waste products
carbon dioxide and urea
when is carbon dioxide produced
carbon dioxide
why is carbon dioxide so dangerous
when it dissolves, it produces acid which effects the enzymes in cells
how do you get rid of CO2
diffuses from cells into blood stream diffuses from blood stream into lungs this air is exhaled
how is urea produced
breakdown of excess amino acids turns into ammonia which turns into urea
where is urea produced
liver
why is urea dangerous
it is poisonous to cells
how do you get rid of urea
kidneys filter it out
3 ways in which you lose water from body
exhaling
sweat
urine
function of kidneys
filters substances like urea from the blood
maintains a healthy water level
how do the kidneys conserve water
you produce very concentrated urine with not that much water