Final answer:
Primary active transport is directly dependent on ATP, while secondary active transport does not directly require ATP. Primary active transport moves ions across a membrane and creates a difference in charge, while secondary active transport relies on the electrochemical gradient established by primary active transport.
Step-by-step explanation:
Primary active transport is directly dependent on ATP, while secondary active transport does not directly require ATP. Primary active transport moves ions across a membrane and creates a difference in charge across that membrane, which is directly dependent on ATP. On the other hand, secondary active transport describes the movement of material that is due to the electrochemical gradient established by primary active transport and does not directly require ATP.