ATP-dependent Pumps And Ion Exchangers (session 3) Flashcards Preview

Semester 1-ICPP > ATP-dependent Pumps And Ion Exchangers (session 3) > Flashcards

Flashcards in ATP-dependent Pumps And Ion Exchangers (session 3) Deck (10):
1

What is the function of the Na+/K+ ATPase pump?

Forms Na+ and K+ gradients necessary for electrical excitability
Drives secondary active transport: control of pHi, regulation of cell volume, absorption of Na+ in epithelia

2

Why is high intracellular [Ca2+] toxic to cells?

Lots of phosphate in cells due to hydrolysis of ATP, calcium+phosphate=calcium phosphate and this leads to ossification

3

What are the primary active transport mechanisms for controlling resting [Ca2+]?

PMCA expels Ca2+ out of the cell
SERCA accumulates Ca2+ into SR/ER

4

What is the secondary active transport mechanism for controlling resting [Ca2+]?

NCX

5

What is the facilitated transport mechanism for controlling resting [Ca2+]?

Mitochondrial Ca2+ uniports

6

How many Na+ and Ca2+ does NCX exchange?

3 Na+ for every 1 Ca2+

7

Give examples of acid extruders in the control of cell pH

Na+/H+ exchanger (NHE)
Na+ dependent Cl-/HCO3- exchanger (NBC=sodium bicarbonate cotransporter)

8

Give an example of a base extruder

Cl-/HCO3- exchanger (AE=anion exchanger)

9

What is NHE inhibited by?

Amiloride (potassium sparing diuretic-stops K+ entering urine)

10

Which enzyme induces apoptosis when [Ca2+] is too high?

Caspases