HUMAN NUTRITION

Detailed explanation-1: -Passive transport requires no energy input, as compounds are able to move freely across the membrane based only on a favourable concentration gradient (Figure 1.11).

Detailed explanation-2: -Diffusion is a passive process which means it does not require energy. Small particles diffuse faster than large ones. Eg substances like oxygen, carbon dioxide and glucose move in and out of cells by diffusion. The greater the difference in concentration, the faster the rate of diffusion.

Detailed explanation-3: -area with lower concentration. The difference between the concentrations is called the “concentration gradient”. Diffusion goes down the gradient until an equilibrium is reached.