relative size of microbes

large microbe

20 µm or 20,000 nm

normal bacterium/mitochondrion

2 µm or 2000 nm (average 1-5 µm)

ribosome

0.02 µm or 20 nm

protein

0.002 µm or 2 nm

1 µm is equal to

1000 nm

small bacteria

200-500 nm

viruses

20-500 µm

yeast

5-10 µm