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: -Primary active transport directly uses a source of chemical energy (e.g., ATP) to move molecules across a membrane against their gradient.

Detailed explanation-3: -Active transport mechanisms require the use of the cell’s energy, usually in the form of adenosine triphosphate (ATP).

Detailed explanation-4: -ATP plays a critical role in the transport of macromolecules such as proteins and lipids into and out of the cell. The hydrolysis of ATP provides the required energy for active transport mechanisms to carry such molecules across a concentration gradient.

Detailed explanation-5: -There are two main types of active transport: Primary (direct) active transport – Involves the direct use of metabolic energy (e.g. ATP hydrolysis) to mediate transport. Secondary (indirect) active transport – Involves coupling the molecule with another moving along an electrochemical gradient.