movement of particles from a low (dilute) solution to a higher (concentrated) solution using energy from respiration
movement of particles in active transport: particles move against the concentration gradient from a low concentration to a high concentration
there is energy required for active transport - energy is released by respiration
active transport in humans:
active transport allows sugar molecules to be absorbed from the small intestine when the sugar concentration is higher in the blood than in the small intestine
active transport in plants:
it is used to absorb mineral ions into the root hair cells from a more dilute solution in the soil
