Final answer:
The mechanism that is NOT a form of active transport from the options provided is unidirectional movement with gradients (option 3), because active transport involves moving substances against their concentration gradient with energy, not along it unidirectionally.
Step-by-step explanation:
The mechanisms of active transport include ATP hydrolysis-driven pumps, coupled transport or co-transport, and light-driven pumps. These mechanisms involve the movement of substances against their concentration gradient, which necessitates the use of cellular energy.
Facilitated diffusion, though it also involves transport proteins, is not a form of active transport because it does not require energy; rather, it relies on the concentration gradient of the substance being transported. Therefore, among the options given:
- Coupled transport (1) is a form of active transport known as secondary active transport.
- ATP hydrolysis-driven pump (2) is an example of primary active transport.
- Unidirectional movement with gradients (3) is not an accurate descriptor of active transport, since active transport often moves substances against gradients.
- Light-driven pumps (4) are a form of active transport found in some photosynthetic organisms.
The mechanisms that are NOT forms of active transport from the options provided would be unidirectional movement with gradients (3). The term unidirectional movement with gradients could describe passive transport mechanisms rather than active transport. The other option, light-driven pumps (4), is actually a mechanism of active transport. Therefore, both (5) is incorrect as it includes an incorrect statement about light-driven pumps. Option 3 is the correct choice that is not a mechanism of active transport.