AP BIOLOGY

Detailed explanation-1: -Answer and Explanation: The driving force of Simple Diffusion is C. Concentration Gradient. A concentration gradient occurs when the concentration in one area is higher than the concentration of another area.

Detailed explanation-2: -Answer and Explanation: The force driving simple diffusion is the concentration gradient, while the energy source for active transport is ATP.

Detailed explanation-3: -There are two main modes of transport of molecules across any biological membrane. These are passive and active transport. 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-4: -The driving force for diffusion is the thermal motion of molecules. At temperatures above absolute zero, molecules are never at rest. Their kinetic energy means that they are always in motion, and when molecules collide with each other frequently, the direction of the motion becomes randomized.

Detailed explanation-5: -The driving force for simple diffusion is the concentration gradient, and membrane potential gradient. In order for molecules to diffuse either in/out of the cell, they have to pass through the hydrophobic core of the lipid bilayer.