AP BIOLOGY

Detailed explanation-1: -In this process of transportation, the energy is utilized by the breakdown of the ATP – Adenosine triphosphate to transport molecules across the membrane against a concentration gradient.

Detailed explanation-2: -Active transport uses energy to transport molecules across the plasma membrane. This uses energy from ATP. They also use pumps to get molecules in or out of the cell. Passive Transport does NOT use energy to transport molecules across the membrane.

Detailed explanation-3: -Active transport mechanisms can be divided into two categories. Primary active transport directly uses a source of chemical energy (e.g., ATP) to move molecules across a membrane against their gradient.

Detailed explanation-4: -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.

Detailed explanation-5: -Primary active transport uses carrier proteins, while secondary active transport uses channel proteins. B. Primary active transport can only transport one substance at a time, while secondary active transport can transport two.