Kidneys: Reabsorbtion Flashcards
What are the three processes of the kidney?
Filtration
Reabsorption
Secretion
As filtrate passes through the tubules, 99% of it is returned to the______ ______, so back to the blood
peritubular capillaries
Both active and ______ processes are at work here
passive
___% of total energy requirements for the kidney is Na+ reabsorption, 6% of calories at rest
80%
What are some things that are reabsorbed?
Na+ K+ Glucose, H20, amino acids
What do we have to do to “move” water? Set a gradient- Surrounding tissues must become _______- need solutes to pull H2O in
hypertonic
In which two places does reabsorption take place?
Glomerulus
Proximal convoluted tubule
What is reabsorbed at the glomerulus?
All plasma solutes except proteins are able to enter the filtrate freely
The solute concentration in the filtrate from the glomerulus is the same as the blood, that is ___-tonic.
Isotonic
How is the isotonic gradient at the glomerulus changed so Na+, Cl- and H2O out of the filtrate?
Na+ and active transport to do this
What is reabsorbed at the PCT?
Water, solutes, Na+, Cl-
What adaptations do the cells of the PCT have to assist reabsorption?
All cells lining the PCT have a brush border microvilli on the apical surface, also have many large mitochondria to produce ATP for active transport
___ reabsorption is critical to everything else
Na+
At the basal portion of PCT cell there are many Na+/K+ pumps. By moving ___ out of the PCT cell into the ECF, there is a permanent low ___ level in the PCT cell. This causes Na+ to diffuse into the ____ from the filtrate.
Na+
Na+
Cell
___ will follow the Na+ into the PCT cell from the filtrate
Cl-
