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 requires chemical energy because it is the movement of biochemicals from areas of lower concentration to areas of higher concentration. Passive transport moves biochemicals from areas of high concentration to areas of low concentration; so it does not require energy. What functions do carrier proteins perform in active transport? Carrier proteins allow molecule to bind to them; they change their shape to transport material across the cell membrane.