Final answer:
The two general types of transport are passive, which requires no energy and moves substances down a concentration gradient, and active, which requires ATP and moves substances against the gradient. Active transport includes primary and secondary types.
Step-by-step explanation:
The two general types of transport mechanisms for cells are passive transport and active transport. Passive transport does not require energy; substances move from an area of higher concentration to a lower concentration, following the concentration gradient.
In contrast, active transport requires cellular energy in the form of ATP because it involves moving substances from an area of lower concentration to a higher concentration, against the concentration gradient.
Primary active transport and secondary active transport are both mechanisms of active transport. Primary active transport directly uses ATP to move ions across a membrane, which creates a difference in charge. Conversely, secondary active transport relies on the electrochemical gradient established by primary active transport but does not directly use ATP.