Diffusion in condensed phases, especially in natural systems such as solutions, geochemical melts and solid–solid interfaces, is an important process that remains poorly understood at a quantitative ...

Diffusion is the movement of particles from a region where they are in high concentration to a region where they are in low concentration, and is one of the ways substances can move across the cell ...

Active transport is a process that is required to move molecules against a concentration gradient. The process requires energy. For plants to take up mineral ions, ions are moved into root hairs, ...