claim the interaction of motrin and robitussin can cause heart attacks in children
Active transport. Active transport is the movement of molecules across a cell membrane from a region of their lower concentration to a region of their higher concentrationâin the direction against some gradient or other obstructing factor (often a concentration gradient).
Active transport (def) is a process whereby the cell uses both transport proteins and metabolic energy to transport substances across the membrane against the concentration gradient. In this way, active transport allows cells to accumulate needed substances even when the concentration is lower outside.