Here's why:
* Concentration Gradient: This refers to the difference in concentration of a substance between two areas. Imagine a room with a lot of perfume in one corner and none in the other. There's a concentration gradient!
* Diffusion: The natural movement of a substance from an area of high concentration to an area of low concentration. In our perfume example, the perfume molecules would naturally spread out, moving from the corner where there are lots of them to the rest of the room where there are fewer.
This movement happens because of the constant random motion of molecules. They collide with each other and move around until they are evenly distributed.
Diffusion is a passive process, meaning it doesn't require energy input. It's a fundamental principle in biology, playing a vital role in everything from the exchange of gases in the lungs to the transport of nutrients within cells.
