osmoregulation Flashcards
what is an osmoreceptor
sensory receptor that detects changes in water potential
what hormone controls permeability of the collecting duct of the kidney
anti diurect hormone
what are sources of water for the body
food
drink
metabolism
if more water is reabsorbed in the body, what is the composition of the urine
lower water potential
low volume of urine
if less water is reabsorbed in body what is composition of the urine
high water potential high volume
on a hot day would more water be reabsorbed or excreted
reabsorbed
where are osmoreceptors located
Hypothalamus
what happens to osmoreceptors when they detect water potential is low
water osmoses out of them and they shrink
Once osmoreceptors shrink, they stimulate another cell as a response. What cell is this
neurosecretory cells
what is a neurosecretory cell
specialised nerve cells/ neurone that produce ADH.
what are characteristics of hormones
travel in blood stream
chemical messenger
longer lasting
slower acting
what happens if antidiurect hormone is high
vesicles containing aquaporins fuse with the membrane of the collecting duct, making it more permeable to water. Allowing more water to enter blood
what happens is ADH levels fall in the blood
membrane of collecting duct folds inwards and creates vesicles with remove aquaporins in the membrane- reducing permeability and restricting water reabsorption
what is the composition of urine when ADH is high
low volume
low water potential
where is ADH manufactured
in the hypothalamus
