Tubular Function Flashcards
What are the transport mechanisms for fluids to cross the tubular cell?
Transcellular Paracellular Antiporter Symporter Uni porter
What is primary and secondary active transport?
Primary- coupled directly to energy source
Secondary - coupled indirectly to an energy source
What is transport maximum?
When capacity of carrier is exceeded
Is the PCT continuous with the Bowman’s space of the Bowman’s capsule and lies entirely in the cortex?
Yes
What is the role of mitochondria in PCT cells?
Supply energy for reabsorption of nutrients electrolytes and other substance which should not be lost from the body
Is the apical membrane permeable to bicarbonate?
No
How does water reabsorption in PCT?
Through leaky junctions and via aquaporins
How does calcium chlorine and potassium passively reabsorb into the PCT?
Paracellulardue to active reabsorption of sodium at basolateral membrane
How is urea reabsorbed?
Reabsorption of water creates conc grad that favours passive reabsorption of urea
What does the early DCT reabsorb?
Sodium potassium out and chlorine
What are the late DCTs and CDs conducted of and reabsorb?
p cells - reabsorb sodium and secrete potassium
I cells - reabsorb potassium and bicarbonate and secrete hydrogen
What are the 5 steps of reabsorption in the tubular function?
1) luminal membrane
2) cytosol
3) basolateral
4) interstitial fluid
5) capillary wall
Where is ADH synthesised and located and where is it transported and stored?
In cells located in hypothalamus and transported in nerve terminals located in posterior pituitary
What is ADH release stimulated by?
Increase in body fluid osmolality and fall in b volume/ pressure
