B12 homeostasis in action Flashcards
thermoregulatory centre
in hypothalamus controls core body temp
contains receptors
cooling down
vasodilation occurs
more energy transferred from skin to surroundings
sweat more- transferring energy
keeping warm
vasoconstriction
sweat less- less energy transferred
shivering by exothermic muscle contractions so energy raises body temperature
erect body hairs trap layer of air around them
carbon dioxide
produced in respiration, acidic when dissolved
would effect working of enzymes
diffuses out of cells down conc gradient from blood to alveoli
removed during exhalation as well as water
urea
breakdown of amino acids in liver
poisonous substance, build up causes cell damage
filtered out of blood by kidneys
removed in urine
deamination
liver removes amino group from amino acids
forming ammonia, toxic
converted into urea before excretion
amino acid molecule used in respiration or to make other molecules
maintaining mineral and water balance
water leaves in exhalation
lost through skin in sweat
excess lost via kidneys in urine(controlled)
also removes urea
kidneys
filters blood and reabsorbs all glucose as well as needed water/minerals
excess removed via urine
selective reabsorption
water balance maintained by adh
adh
less ADH-more urine, less reabsorption
more ADH- less urine, more reabsorption