AP BIOLOGY

Detailed explanation-1: -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-2: -Passive transport: This does not require any energy expenditure as it occurs along the concentration gradient of the molecule being translocated. Examples include simple diffusion, facilitated diffusion, and osmosis.

Detailed explanation-3: -area with lower concentration. The difference between the concentrations is called the “concentration gradient”. Diffusion goes down the gradient until an equilibrium is reached.

Detailed explanation-4: -Because the transport process uses ATP as an energy source, it is considered an example of primary active transport.