Which is faster simple diffusion or facilitated diffusion?

Facillatated diffusion is faster than simple diffusion when solute concentration is low because it uses channels to transport molecules throught the lipid bilayer. Simple diffusion depends upon concentration gradients so the net movement of diffusing molecules depends on the concentration gradient, thus the rate of diffusion is directly proportional to the concentration gradient.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms