Answer:
Primary active transport
Explanation:
In primary active transport, ATP is used to transport the molecules of ions against their concentration gradient. One of the examples of primary active transport is sodium-potassium pump which transports sodium and potassium ions across the cell membrane.
The energy released by the breaking of the high energy phosphate bond in ATP gives the energy to transporter protein to transport these ions across cells which is not possible in passive transport because passive transport only occurs along the concentration gradient.
