AP BIOLOGY

Detailed explanation-1: -Active transport is the movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration-against the concentration gradient. Active transport requires cellular energy to achieve this movement.

Detailed explanation-2: -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).

Detailed explanation-3: -Passive transport is a naturally occurring phenomenon and does not require the cell to expend energy to accomplish the movement. In passive transport, substances move from an area of higher concentration to an area of lower concentration in a process called diffusion.

Detailed explanation-4: -Osmosis: Osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution.