Passive Diffusion

Most lipophilic substances can, for example, be absorbed by the intestinal epithelial cells by simple diffusion. In simple diffusion, only the dissolved particles migrate through the membrane, no energy is required. In contrast to diffusion, in filtration the solution medium and not only the dissolved particles pass through the membrane. A concentration balance is also aimed at here, as long as the membrane pores are coarse enough so that the particles can pass freely. Classic filtration takes place in the glomeruli of the kidneys.