AP BIOLOGY

Detailed explanation-1: -During active transport, substances move against the concentration gradient, from an area of low concentration to an area of high concentration. This process is “active” because it requires the use of energy (usually in the form of ATP). It is the opposite of passive transport.

Detailed explanation-2: -“Active Transport is defined as a process that involves the movement of molecules from a region of lower concentration to a region of higher concentration against a gradient or an obstacle with the use of external energy.”

Detailed explanation-3: -If movement is with the concentration or gradient, it is passive. If movement is against the gradient, it is active and requires energy.

Detailed explanation-4: -The movement of ions or molecules against a concentration gradient with the utilisation of energy is known as active transport.

Detailed explanation-5: -There are two main modes of transport of molecules across any biological membrane. These are passive and active transport. Passive transport, most commonly by diffusion, occurs along a concentration gradient from high to low concentration. No energy is necessary for this mode of transport.