mitochondrion

noun
mi·​to·​chon·​dri·​on | \ ˌmī-tə-ˈkän-drē-ən How to pronounce mitochondrion (audio) \
plural mitochondria\ ˌmī-​tə-​ˈkän-​drē-​ə How to pronounce mitochondrion (audio) \

Definition of mitochondrion

: any of various round or long cellular organelles of most eukaryotes that are found outside the nucleus, produce energy for the cell through cellular respiration, and are rich in fats, proteins, and enzymes — see cell illustration

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Other Words from mitochondrion

mitochondrial \ ˌmī-​tə-​ˈkän-​drē-​əl How to pronounce mitochondrion (audio) \ adjective

Examples of mitochondrion in a Sentence

Recent Examples on the Web The study propelled Chandel, then at the University of Chicago, and his colleagues to examine whether mitochondria could release other signals as well. Quanta Magazine, "Biologists Discover Unknown Powers in Mighty Mitochondria," 18 Mar. 2019 For decades, researchers have known that mitochondria are derived from bacteria that became internal symbionts of archaeal cells, but details of how that happened have been sketchy. Quanta Magazine, "Researchers Rethink the Ancestry of Complex Cells," 9 Apr. 2019 But the researchers think that the absence of a functioning mitochondrion might be linked to the peculiar environment where the parasite lives — fish muscle. Veronique Greenwood, New York Times, "This Parasite Doesn’t Need Oxygen to Survive," 28 Feb. 2020 The mitochondria are like factories that manufacture ATP. Joshua Selsby, CNN, "White meat, or dark meat? The science behind a delicious debate," 27 Nov. 2019 This is not the first time researchers have found creatures that have ditched their mitochondria. Veronique Greenwood, New York Times, "This Parasite Doesn’t Need Oxygen to Survive," 28 Feb. 2020 The mitochondria are the remains of what were once free-living bacteria, incorporated inside the cell and adapted for the production of the chemical energy source ATP. John Timmer, Ars Technica, "Researchers find an animal without mitochondria," 26 Feb. 2020 The mitochondria are like factories that manufacture ATP. Joshua Selsby, CNN, "White meat, or dark meat? The science behind a delicious debate," 27 Nov. 2019 In L’Engle’s world, even something as microscopic as a mitochondrion can have cosmic significance, and a child can save the universe. Ruth Franklin, The New York Review of Books, "L’Engle’s Cosmic Catechism," 25 Feb. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mitochondrion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mitochondrion

1901, in the meaning defined above

History and Etymology for mitochondrion

borrowed from German (in plural Mitochondria), from Greek mítos "length of thread, cord used to separate warp threads" (of uncertain origin) + -o- -o- + chóndrion "granule," diminutive of chóndros "grain, groats" — more at chondro-

Note: Term introduced by the German microbiologist Carl Benda (1857-1932) in "Ueber die Spermatogenese der Vertebraten und höherer Evertebraten: II. Theil: Die Histiogenese der Spermien" [XVII. Sitzung am 29. Juli 1898], Archiv für Anatomie und Physiologie - Physiologische Abtheilung, Jahrgang 1898, p. 397: "Sie liegen innerhalb eines Theiles der Protoplasmafäden, bisweilen zu besonderen Körpern gehäuft, und sind wenigsten mit einem Theil der bereits bekannten Zellmikrosomen identisch, aber unterschieden von den Altmann'schen und Ehrlich'schen Granulationen. Ich möchte vorläufig vorschlagen, ihnen als Mitochondria eine besondere Stellung vorzubehalten, die ich in weiteren Arbeiten begründen werde." ("They lie within of a portion of the protoplasmic threads, sometimes aggregated to particular bodies, and are identical to at least part of the already known cell microsomes, but differ from Altmann's and Ehrlich's granulations. I would like to suggest tentatively reserving for them a special status as mitochondria, which I will substantiate in further work.")

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Time Traveler for mitochondrion

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The first known use of mitochondrion was in 1901

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Cite this Entry

“Mitochondrion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mitochondrion. Accessed 10 Apr. 2021.

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More Definitions for mitochondrion

mitochondrion

noun
mi·​to·​chon·​dri·​on | \ ˌmī-tə-ˈkän-drē-ən How to pronounce mitochondrion (audio) \
plural mitochondria\ -​drē-​ə \

Kids Definition of mitochondrion

: one of the parts found in the cytoplasm of a cell outside the nucleus that provides the cell with energy released from the breakdown of nutrients

mitochondrion

noun
mi·​to·​chon·​dri·​on | \ ˌmīt-ə-ˈkän-drē-ən How to pronounce mitochondrion (audio) \
plural mitochondria\ -​drē-​ə How to pronounce mitochondrion (audio) \

Medical Definition of mitochondrion

: any of various round or long cellular organelles of most eukaryotes that are found outside the nucleus, produce energy for the cell through cellular respiration, and are rich in fats, proteins, and enzymes

called also chondriosome

Other Words from mitochondrion

mitochondrial \ -​drē-​əl How to pronounce mitochondrion (audio) \ adjective
mitochondrially \ -​ē How to pronounce mitochondrion (audio) \ adverb

More from Merriam-Webster on mitochondrion

Britannica.com: Encyclopedia article about mitochondrion

Comments on mitochondrion

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