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: -There is a form of passive transport called facilitated diffusion. It occurs when molecules such as glucose or amino acids move from high concentration to low concentration facilitated by carrier proteins or pores in the membrane.

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: -Active transport, simply put, is the movement of particles through a transport protein from low concentration to high concentration at the expense of metabolic energy.

Detailed explanation-5: -The most famous example of a primary active transport protein is the sodium-potassium pump. It is this pump that creates the ion gradient that allows neurons to fire. The sodium-potassium pump begins with its sodium binding sites facing the inside of the cell.