Sizes of pathogensWatch this thread
Ive been trying to find an answer for this on the internet.
What is the order of size between protist fungi bacteria and viruses.
Most viruses are composed of little more than a nucleic acid core plus protein molecules. They are therefore very tiny.
Bacteria have no nucleus and often comparatively little in the way of internal structure. They are tiny.
Protists are unicellular but have a true nucleus and often complex intracellular structure. They are very small, but some are just visible to the naked eye.
Fungi are multicellular. Some are small, others large.