photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfō-tō-ˈsin(t)-thə-səs How to pronounce photosynthesis (audio) \

Definition of photosynthesis

: synthesis of chemical compounds with the aid of radiant energy and especially light especially : formation of carbohydrates from carbon dioxide and a source of hydrogen (such as water) in the chlorophyll-containing cells (as of green plants) exposed to light

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Other Words from photosynthesis

photosynthesize \ ˌfō-​tō-​ˈsin(t)-​thə-​ˌsīz How to pronounce photosynthesize (audio) \ intransitive verb
photosynthetic \ ˌfō-​tō-​sin-​ˈthe-​tik How to pronounce photosynthetic (audio) \ adjective
photosynthetically \ ˌfō-​tō-​sin-​ˈthe-​ti-​k(ə-​)lē How to pronounce photosynthetically (audio) \ adverb

Photosynthesis Has Greek Roots

The Greek roots of photosynthesis combine to produce the basic meaning "to put together with the help of light". Photosynthesis is what first produced oxygen in the atmosphere billions of years ago, and it's still what keeps it there. Sunlight splits the water molecules (made of hydrogen and oxygen) held in a plant's leaves and releases the oxygen in them into the air. The leftover hydrogen combines with carbon dioxide to produce carbohydrates, which the plant uses as food—as do any animals or humans who might eat the plant.

Examples of photosynthesis in a Sentence

Recent Examples on the Web

There’s no requirement to be big or small, organic or conventional.’’ At the core is the idea that plants breathe, and through the process of photosynthesis turn carbon dioxide from the atmosphere into sugars that become leaves, stems and roots. Laura Reiley, BostonGlobe.com, "A Boston company’s plan to remove a trillion tons of carbon dioxide from the atmosphere: Bury it.," 13 June 2019 The overall entropy of the universe increases during photosynthesis as the sunlight dissipates, even as the plant prevents itself from decaying by maintaining an orderly internal structure. Quanta Magazine, "A New Physics Theory of Life," 22 Jan. 2014 When the sun sets or the lights go out, photosynthesis stops. Heidi Mitchell, WSJ, "Which Houseplants Grow Best in Low Light?," 10 Nov. 2018 The nanotube method is far more elegant and even managed to insert genes into chloroplasts, the organelles in plant cells responsible for photosynthesis. Jill Kiedaisch, Popular Mechanics, "An Advance in Bioengineering Could Pave the Way for Tomorrow’s Superplants," 12 Mar. 2019 During photosynthesis, the chlorophyll in the phytoplankton absorbs the blue light on the spectrum, making algae-rich regions appear greener. Jill Kiedaisch, Popular Mechanics, "Half of the World's Oceans Will Change in Color by the End of this Century," 5 Feb. 2019 The study points out that abundant surface life on Earth was only possible after cyanobacteria evolved to engage in oxygen-producing photosynthesis, about 1.5 billion years after the first life formed on Earth, which was roughly 4 billion years ago. Jay Bennett, Popular Mechanics, "Martian Fossils Could Be Found Near Long-Buried Hydrothermal Vents," 26 Dec. 2017 Semi-artificial photosynthesis, a relatively new field of study, aims to address those concerns by combining manmade technologies with biological processes in order to mimic nature’s method of splitting water into oxygen and hydrogen. Fox News, "Scientists invent way to create 'unlimited renewable energy'," 7 Sep. 2018 Some new development like photosynthesis, some new surprise like an asteroid or a belch of volcanic carbon, throws a monkey wrench into the world order. Robert M. Thorson, WSJ, "‘Timefulness’ Review: Thinking in Eons," 30 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'photosynthesis.' 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 photosynthesis

1898, in the meaning defined above

History and Etymology for photosynthesis

New Latin

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Statistics for photosynthesis

Last Updated

23 Jun 2019

Look-up Popularity

Time Traveler for photosynthesis

The first known use of photosynthesis was in 1898

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More Definitions for photosynthesis

photosynthesis

noun

English Language Learners Definition of photosynthesis

biology : the process by which a green plant turns water and carbon dioxide into food when the plant is exposed to light

photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfō-tə-ˈsin-thə-səs How to pronounce photosynthesis (audio) \

Kids Definition of photosynthesis

: the process by which green plants and a few other organisms (as some protists) form carbohydrates from carbon dioxide and water in the presence of light

Other Words from photosynthesis

photosynthetic \ -​sin-​ˈthe-​tik \ adjective photosynthetic activity

photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfōt-ō-ˈsin(t)-thə-səs How to pronounce photosynthesis (audio) \
plural photosyntheses

Medical Definition of photosynthesis

: synthesis of chemical compounds with the aid of light sometimes including the near infrared or near ultraviolet especially : the formation of carbohydrates from carbon dioxide and a source of hydrogen (as water) in chlorophyll-containing cells (as of green plants) exposed to light involving a photochemical release of oxygen through the decomposition of water followed by various enzymatic synthetic reactions that usually do not require the presence of light

Other Words from photosynthesis

photosynthesize \ -​ˌsīz How to pronounce photosynthesize (audio) \ also British photosynthesise intransitive verb photosynthesized also British photosynthesised; photosynthesizing also British photosynthesising
photosynthetic \ -​sin-​ˈthet-​ik How to pronounce photosynthetic (audio) \ adjective
photosynthetically \ -​i-​k(ə-​)lē How to pronounce photosynthetically (audio) \ adverb

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More from Merriam-Webster on photosynthesis

Spanish Central: Translation of photosynthesis

Nglish: Translation of photosynthesis for Spanish Speakers

Britannica.com: Encyclopedia article about photosynthesis

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