Which one of the following is active transport?
1
It is the movement of a substance against a diffusion gradient with the use of energy from respiration.
2
It is the movement of a substance against a diffusion gradient without the use of energy.
3
It is the movement of a substance against a diffusion gradient with the use of energy from photosynthesis.
4
It is the movement of a substance along a diffusion gradient with the use of energy from respiration.