Osmoregulation

Question 1

Where is water balanced

Answer 1

In distal convoluted tube and collecting duct
Permeability can be altered

Question 2

Water loss hormone

Answer 2

Anti diuretic hormone
Produced by hypothalamus
Secreted by posterior pituitary gland

Question 3

Adh storage

Answer 3

In vesicles in axon terminals
At the posterior pituitary gland

Question 4

How is water potential monitored

Answer 4

By cells in hypothalamus called osmoreceptors

Question 5

ADH action stage 1

Answer 5

Released from ppt into blood
Travels to collecting duct of the kidneys
Binds to receptors in cell membrane of tubule cells

Question 6

ADH action stage 2

Answer 6

Binding triggers cAMP
Triggers cascade of events

Question 7

cAMP triggers….

Answer 7

Vesicles to fuse to collecting duct membrane containing aquaporins
Water then travels out collecting duct into medulla then into the blood

Question 8

Drinking a lot

Answer 8

Water potential of blood rises
ADH levels fall levels of cAMP fall
Water channels enclosed in vesicles
Collecting duct is impermeable
Result in production of large volume of dilute urine
Maintains wp of blood and tissue fluid