| A | B |
|---|
| anaerobic respiration | use of inorganic molecules other than oxygen to accept electrons |
| biofilm | surface-coating colony of prokaryotes that engage in metabolic cooperation |
| bioremediation | use of living organisms to detoxify and restore polluted and degraded ecosystems |
| capsule | sticky layer that surrounds the cell walls of some bacteria |
| chemoautotroph | organism that needs only carbon dioxide as a carbon source but that obtains energy by oxidizing inorganic substances |
| chemoheterotroph | organism that must consume organic molecules for both energy and carbon |
| commensalism | symbiotic relationship where symbiont benefits but the host is neither helped nor harmed |
| decomposer | absorb nutrients from nonliving organic material such as corpses and convert them into inorganic forms |
| endospore | thick-coated |
| endotoxin | component of the outer membrane responsible for generalized symptoms of fever and ache |
| exotoxin | toxic protein made by a bacterial cell and that produces symptoms in the absence of bacterium |
| extreme halophile | microorganism that lives in an unusually saline environment |
| extreme thermophile | microorganism that thrives in hot environments |
| extremeophile | microorganism that lives in an extreme environment |
| facultative anaerobe | makes ATP by aerobic respiration if oxygen can do fermentation under anaerobic conditions |
| fimbria | short |
| Gram stain | distinguishes between two different kinds of bacterial cell walls |
| gram-negative | group of bacteria with a structurally more complex cell wall made of less peptidoglycan |
| gram-positive | group of bacteria with simpler cell walls with a relatively large amount of peptidoglycan |
| host | larger participant in a symbiotic relationship |
| methanogen | microorganism that obtains energy by using carbon dioxide to oxidize hydrogen |
| mutualism | symbiotic relationship in which both participants benefit |
| nitrogen fixation | assimilation of atmospheric nitrogen by prokaryotes into nitrogenous compounds usable by plants |
| nucleoid region | region in a prokaryotic cell consisting of a concentrated mass of DNA |
| obligate aerobe | requires oxygen for cellular respiration and cannot live without it |
| obligate anaerobe | organism that cannot use oxygen and is poisoned by it |
| parasite | organism that absorbs nutrients from the body fluids of living hosts |
| parasitism | symbiotic relationship in which the symbiont (parasite) benefits at the expense of the host |
| endoparasitism | parasite that lives within the host organism |
| ectoparasite | parasite that lives outside of the host organism |
| peptidoglycan | polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides |
| photoautotroph | organism that harnesses light energy to drive the synthesis of organic compounds from carbon dioxide |
| photoheterotroph | organism that uses light to generate ATP but that must obtain carbon in organic form |
| pilus | hairlike prokaryotic appendage that functions in adherence or in the transfer of DNA during conjugation |
| plasmid | small ring of DNA that carries accessory genes separate from those of a bacterial chromosome |
| symbiont | smaller participant in a symbiotic relationship |
| symbiosis | organisms of two different species that live together in direct contact |
| taxis | Movement toward or away from a stimulus |
