Simple Definition For Passive Diffusion

Passive diffusion refers to the movement of ions or molecules across the cell membrane through a concentration gradient without utilizing the cellular energy.

Simple definition for passive diffusion. Lipid soluble drugs penetrate lipid membranes with ease. Passive diffusion is the process by which molecules diffuse from a region of higher concentration to a region of lower concentration. This technology may be used to develop nutrient management thresholds for streams based on comprehensive measures of nutrient assimilative capacity. It s like moving from the train to the platform of a subway station or stepping out of a crowded room.

Passive diffusion is the simplest unregulated method for a substance to cross the membrane. This cartoon illustrates passive diffusion. It is the most important mechanism for passage of drugs through membranes. Simple diffusion is a type of passive transport which as the name suggests is simply the movement of solute which occurs when its electrochemical potentials on the two sides of a permeable barrier are different.

This is a spontaneous process and cellular energy is not expended. Simple diffusion is the movement of molecules through a cell membrane without using the channels formed by integral membrane protein. Substances of the right size and chemical class small non polar uncharged particles pass through the membrane unassisted by taking advantage of imperfect nature of the phospholipid bilayer. Therefore passive diffusion uses the natural entropy of the molecules to pass through the cell membrane.

For example a passive diffusion periphytometer is used to assess algal nutrient limitation and assimilation capacity in streams. Facilitated diffusion is the movement of molecules through those channels. 6 votes see 1 more reply.