Facilitated diffusion is the process of moving molecules across the membrane with the help of transport proteins to make the transportation of the molecules a lot easier and smoother.
Simple diffusion, however, does not have the assistance of transport proteins. Simple diffusion takes place when molecules move from a high concentration (of said molecule) to a low concentration.
The difference: Facilitated diffusion has the help of transport proteins while simple diffusion does not.
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At least 75% of the history of the earth
A hypothesis is considered scientific if it has something that can be supported or refuted through carefully crafted experimentation or observation