Renal 5 Flashcards
mass balance
whatever comes in must be excreted if not needed
what determines ECF volume and osmolarity
H2O and Na
what determines the bodies pH
H and HCO3
why is maintaining osmolarity within the body important
water can cross most cell membranes freely and easily affect cell volume
what kind of osmolarity are renal tubes always exposed to ? how do they deal with it
hypertonic ECF
thy produce organic solutes to match the intracellular osmolarity to the ECF
what systems does fluid and electrolyte balance use (4)
respiratory
cardiovascular
renal systems
behavioural responses
what systems are fast in the fluid and electrolyte balance equilibrium
cardiovascular
respiratory
what systems are slow in fluid and electrolyte balance control
renal
what control are the kidneys under
endocrine and neuroendocrine control
how much of water makes up our body weight
50-60%
what are the 2 ways water can be gained
food and drink
metabolism
how is water lost? (4)
skin
lungs
urine
feces
can the kidneys replace water that’s lost to the environment
no
how must volume loss be replaced
behavioural mechanisms to maintain homeostasis
what mainly controls production of urine
the renal medulla
what is the removal of excess urine called
diuresis
when removal of excess water is required, the kidneys produce large volume of
dilute urine
if the kidneys need to conserve water, low volume of ________ _______ is produced
concentrated urine
how do the kidneys control urine concentration
varying the mounts of water and Na reabsorbed in the distal nephron
where is water reabsorbed
descending loop
what allows water permeability but not solutes
descending loop
what limb allows ion reabsorption but not water
ascending
what does urine osmolarity depend on
reabsorption in the collecting duct
what does vasopressin control
water reabsorption
