Working Against the Concentration Gradient Pumps are a kind of active transport which pump ions and molecules against their concentration gradient. … The protein channels that undergo passive transport work against the pump, allowing sodium ions to enter the cell constantly, so the pumps work to remove the excess ions.

Why do cells need pumps?

The pump is found in the plasma membrane of almost every human cell and is common to all cellular life. It helps maintain cell potential and regulates cellular volume. It is also important for the conduction of electrical impulses along nerve cells.

What is the purpose of membrane pumps?

Protein pumps transport ions and other solutes across membranes up concentration gradients as great as 1 million-fold. Energy for this task can come from a variety of sources: light, oxidation-reduction reactions, or, most commonly, hydrolysis of ATP (Table 8-1).