| A | B |
| prokaryote | cell lacks a nuclear membrane |
| unicellular | organism is made of only one cell |
| flagellum | whiplike tail used by some bacteria to move |
| cyanobacteria | organisms in Kingdom Eubacteria that contain chlorophyll |
| coccus | round bacteria |
| bacillus | rod-shaped bacteria |
| spirillum | spiral-shaped bacteria |
| filament | chain of cyanobacteria living together |
| colony | group of cyanobacteria living together |
| Anabaena | cyanobacteria that forms filaments |
| Gloeocapsa | cyanobacteria that forms colonies |
| Nostoc | cyanobacteria that forms filaments (not smooth) |
| Oscillatoria | cyanobacteria that forms smooth filaments |
| pathogens | organisms that cause disease |
| saprophytes | helpful bacteria that use dead organisms and waste as food |
| fission | most bacterial reproduce by splitting in two |
| chromosome | strand of DNA molecules |
| vaccine | prevents some bacterial diseases |
| antibiotic | drug that can kill bacteria |
| blue-green bacteria | common name for cyanobacteria |
| chlorophyll | green pigment needed for photosynthesis that traps the sun's energy |
| pasteurization | heating to a temperature that kills bacteria |
| toxins | poisons that some pathogens produce |
| endospores | thick walled heat resistance structures that can surround some bacteria |
| bacteria | unicellular prokaryotes in Kingdom Eubacteria that do not contain chlorophyll |
| botulism | food poisoning caused by a bacterial toxin |
| aerobe | an organism that uses oxygen for respiration |
| anaerobe | an organism that lives without oxygen |
| nitrogen-fixing | change nitrogen to a form used by plants |
| nodules | growths on the roots of some plants where nitrogen-fixing bacteria live |
| archaeans | unicellular prokaryotes in Kingdom Archaea |