AP BIOLOGY

Detailed explanation-1: -Passive transport does not require the cell to expend any energy and involves a substance diffusing down its concentration gradient across a membrane.

Detailed explanation-2: -Passive transport, most commonly by diffusion, occurs along a concentration gradient from high to low concentration. No energy is necessary for this mode of transport.

Detailed explanation-3: -There are two major ways that molecules can be moved across a membrane, and the distinction has to do with whether or not cell energy is used. Passive mechanisms like diffusion use no energy, while active transport requires energy to get done.

Detailed explanation-4: -This statement is false. Passive transport does not require energy, and active transport does. Passive and active transport both utilize transport proteins to move substances across a cell membrane.

Detailed explanation-5: -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.