adenovirus aerobe aerobic bacteria amoeba anaerobe anaerobic bacteria bacillus bacteria bacterium basidium bug coccus cystocarp disease-producing microorganism echovirus enterovirus filterable virus fungus germ gram-negative bacteria gram-positive bacteria macrospore megaspore microbe microorganism microsporangium microspore mold nonfilterable virus pathogen picornavirus planospore protozoa protozoon reovirus rhinovirus rickettsia sorus spirillum spirochete sporangium sporocarp sporocyst sporocyte sporophore sporophyte sporule staphylococcus streptococcus swarm spore trypanosome vibrio virus zoospore zygospore