Assertion : Facilitated diffusion is more rapid than simple diffusion.
Reason : Facilitated diffusion involves expenditure of energy unlike simple diffusion.
Facilitated diffusion is a passive physical process, not needing expenditure of energy or active cellular participation. Like simple diffusion, this process also depends on a higher concentration of the substance in the intestinal contents than in the intestinal cell or blood, but the process is more rapid than simple diffusion because the substance is carried across the membrane in combination with some carrier molecule of the membrane. Facilitated diffusion can not absorb a substance completely from the intestine. Some nutrients such as fructose and mannose are absorbed from the intestine by this process.