Bacteria, Single-celled organisms. Some are helpful (e.g. digesting food) while some are harmful (e.g. causing disease)., Virus, Non-living particles that need a ‘host’ cell to reproduce. Examples are the common cold and flu., Fungus, Can be single-celled (like Yeast) or multicellular (like mushrooms). They play a role in decomposition and can cause infections., Protozoa/Protoctist, Single-celled organism. Some cause disease, like Malaria..

Leaderboard

Visual style

Options

Switch template

)
Continue editing: ?