ATP Pumps

ATP DRIVEN PUMPS

Primary Active Transport

ATP hydrolysis fuels transport

Sodium-potassium pump

• Na+ electrochemical gradient: large and directed into cell
• K+ electrochemical gradient: small (chemical and electrical gradients oppose each other) and directed out of the cell
• Pumps K+ and Na+ against their gradients
• Hydrolyzes ATP (account for 30% of animal cell's ATP consumption)

Coupled transporters

Couple movement of one solute against its gradient with movement of another solute down its gradient

Light-driven pumps

Occur in bacteria and couple active transport with light energy