Flux (biology)

In general, flux in biology relates to movement of a substance between compartments. There are several cases where the concept of flux is important.

Flux is the net movement of particles across a specified area in a specified period of time. The particles may be ions or molecules, or they may be larger, like insects, muskrats or cars. The units of time can be anything from milliseconds to millennia. Flux is not the same as velocity or speed nor is it the same as density or concentration. Movement itself is not enough.

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