What is a colony forming unit and why can it be used to count viable cells in a sample?

A
colony-forming unit, CFU, is the cell or cells that reproduce on a petri dish that result in a
visible colony.

When bacterial cells from a culture are
placed on a petri dish in a medium with nutrients, oxygen, ambient temperature, etc., the goal
is to grow the microscopic cells into colonies that can be seen. When these colonies
are...

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