Facultative anaerobic organism - wikipedia Facultative anaerobic organism Aerobic and anaerobic bacteria can be identified by growing them in test tubes of thioglycollate broth : 1 : Obligate aerobes need oxygen because they can not ferment or respire anaerobically. They gather at the top of the tube where the oxygen concentration is highest. 2 : Obligate anaerobes are poisoned by oxygen, so they gather at the bottom of the tube where the oxygen concentration is lowest. 3 : Facultative anaerobes can grow with or without oxygen because they can metabolise energy aerobically or anaerobically. They gather mostly at the top because aerobic respiration generates more ATP than either fermentation or anaerobic respiration. 4 : Microaerophiles need oxygen because they can not ferment or respire anaerobically. However, they are poisoned by high concentrations of oxygen. They gather in the upper part of the test tube but not the very top. 5 : Aerotolerant organisms do not require oxygen as they metabolise energy anaerobically. Unlike obligate anaerobes however, they are not poisoned by oxygen. They can be found evenly spread throughout the test tube. A facultative anaerobe is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation or anaerobic respiration if oxygen is absent. An obligate aerobe, by contrast, can not make ATP in the absence of oxygen, and obligate anaerobes die in the presence of oxygen. Some examples of facultative anaerobic bacteria are Staphylococcus spp., Streptococcus spp., Escherichia coli, Salmonella, Listeria spp. and Shewanella oneidensis. Certain eukaryotes are also facultative anaerobes, including fungi such as Saccharomyces cerevisiae and many aquatic invertebrates such as Nereid ( worm ) polychaetes. See also Aerobic respiration Anaerobic respiration Fermentation Obligate aerobe Obligate anaerobe Microaerophile References Jump up ^ Hogg, S. ( 2005 ). Essential Microbiology ( 1st ed. ). Wiley. pp. 99 -- 100. ISBN 0 - 471 - 49754 - 1. Jump up ^ Prescott LM, Harley JP, Klein DA ( 1996 ). Microbiology ( 3rd ed. ). Wm. C. Brown Publishers. pp. 130 -- 131. ISBN 0 - 697 - 29390 - 4. Jump up ^ Ryan KJ ; Ray CG, eds. ( 2004 ). Sherris Medical Microbiology ( 4th ed. ). McGraw Hill. pp. 261 -- 271, 273 -- 296. ISBN 0 - 8385 - 8529 - 9. Jump up ^ Singleton P ( 1999 ). Bacteria in Biology, Biotechnology and Medicine ( 5th ed. ). Wiley. pp. 444 -- 454. ISBN 0 - 471 - 98880 - 4. Jump up ^ Carlile MJ, Watkinson SC, Gooday GW ( 2001 ). The Fungi ( 2nd ed. ). Academic Press. pp. 85 -- 105. ISBN 0 - 12 - 738446 - 4. Jump up ^ Schöttler, U. ( November 30, 1979 ). `` On the Anaerobic Metabolism of Three Species of Nereis ( Annelida ) '' ( PDF ). Marine Ecology Progress Series. 1 : 249 -- 54. ISSN 1616 - 1599. doi : 10.3354 / meps001249. Retrieved February 14, 2010. External links Facultative Anaerobic Bacteria Obligate Anaerobic Bacteria Anaerobic Bacteria and Anaerobic Bacteria in the decomposition ( stabilization ) of organic matter. Microbiology : Bacteria Medical microbiology infection Coley 's toxins Exotoxin Lysogenic cycle Pathogenic bacteria resistance Biochemistry and ecology Oxygen preference Aerobic Obligate Anaerobic Facultative Obligate Microaerophile Nanaerobe Aerotolerant Other Microbial metabolism Primary nutritional groups Nitrogen fixation Microbial ecology Human flora Gut Lung Mouth Skin Vaginal ( In pregnancy ) Placental Uterine Salivary Substrate preference Lipophilic Saccharophilic Shape Bacterial cellular morphologies L - form bacteria Coccus Diplococcus Bacillus Coccobacillus Spiral Structure Cell envelope Cell membrane Cell wall : Peptidoglycan NAM NAG DAP Gram - positive bacteria only : Teichoic acid Lipoteichoic acid Endospore Gram - negative bacteria only : Bacterial outer membrane Porin Lipopolysaccharide Periplasmic space Mycobacteria only : Arabinogalactan Mycolic acid Outside envelope Bacterial capsule Slime layer S - layer Glycocalyx Pilus Fimbria Non-motile bacteria Composite Biofilm Taxonomy Bacteria ( classifications ) Bacterial phyla Former groupings : Schizomycetes Monera Prokaryota Gracilicutes Firmicutes Mollicutes Mendosicutes Retrieved from `` https://en.wikipedia.org/w/index.php?title=Facultative_anaerobic_organism&oldid=800933860 '' Categories : Anaerobic digestion Cellular respiration Talk About Wikipedia Català Eesti Español Euskara فارسی 한국어 Bahasa Indonesia עברית Magyar Nederlands 日本 語 Polski Русский Suomi Svenska Türkçe Українська 中文 Edit links This page was last edited on 16 September 2017, at 16 : 48. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: an organism that cannot grow without oxygen is a(n)
Answer: anaerobe