AP BIOLOGY

Detailed explanation-1: -Facilitated diffusion is the passive movement of substances, such as biological molecules or ions, across a plasma membrane by means of a transport protein located in the plasma membrane. Since the movement of substances is from greater to lesser concentrations, chemical energy is neither used nor required.

Detailed explanation-2: -Facilitated diffusion does not need any energy for the movement of molecules as they move from higher concentration to lower concentration gradient.

Detailed explanation-3: -Simple diffusion does not require energy: facilitated diffusion requires a source of ATP.

Detailed explanation-4: -Facilitated Diffusion Requires Membrane Carrier Proteins Facilitated diffusion is also calledcarrier-mediated diffusion because a substance transported in this manner diffuses through the membrane with the help of a specific carrier protein.

Detailed explanation-5: -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.