Na/K/Cl

Question 1

Concentrations of Na/K/Cl inside and outside of the cell

Answer 1

Na+ outside: 135-148mmol/L inside: 12mmol/L
Cl- outside: 98-108mmol/L inside: 2 mmol/L
K+ outside: 3.8-5.5mmol/L inside 150mmol/L

Question 2

What is the electrical gradient of the cell like?

Answer 2

Negatively charged cytoplasm (because Na+ and K+ are of equal charge but more Na+ are transported outside compared to K+ transported inside)

Question 3

How does Cl- enter the cell?

Answer 3

Through cotransport of Na+ or via paracellular space

Question 4

What is resting membrane potential of the cell?

Answer 4

-70Mv

Question 5

Hyperkalemia

Answer 5

Membrane cannot repolarize

Question 6

How can infection increase water loss?

Answer 6

Bacterial toxins in the GI increase NaCl secretion from crypt cells of SI into lumen, which becomes hyperosmotic and water diffuses into the lumen

Question 7

How does decreased blood pressure affect renal regulation?

Answer 7

Decreased blood pressure or dehydration (hypovolemia) causes release of aldosterone and ADH to conserve water

Question 8

ADH

Answer 8

Increases water reabsorption by insertions of aquaporin-2

Acts of distal convoluted tubule and collecting duct

Question 9

Aldosterone

Answer 9

Conserves water by reabsorption of Na+, using Na/K exchange channels. Results in water reabsorption by water following Na+ and K+ excretion.

Acts of distal convoluted tubule and collecting duct

Question 10

Aquaporin-3

Answer 10

Allows water to move across basolateral membrane from cell to capillary