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n. Symbol O
A nonmetallic element constituting 21 percent of the atmosphere by volume that occurs as a diatomic gas, O2, and in many compounds such as water and silica, and in iron ore. It combines with most elements, is essential for plant and animal respiration, and is required for nearly all combustion. Ozone, O3, is an allotrope of this element. Atomic number 8; atomic weight 15.9994; melting point -218.79°C; boiling point -182.9°C; gas density at 0°C 1.429 grams per liter; valence 2. See Periodic Table.

[French oxygène : Greek oxus, sharp, acid; see ak- in Indo-European roots + French -gène, -gen.]

ox′y·gen′ic (-jĕn′ĭk) adj.
ox′y·gen′i·cal·ly adv.
ox·yg′e·nous (ŏk-sĭj′ə-nəs) adj.
Word History: One of the most important substances on earth is misnamed. The word oxygen is the Anglicized form of French oxygène, the name for the element proposed in a work entitled Méthode de nomenclature chimique (1787) by a collaborative of chemists including Antoine Laurent Lavoisier, Louis Bernard de Guyton de Morveau, Claude Louis Berthollet, and Antoine François de Fourcroy. (Oxygen had been discovered a few years before by Joseph Priestley in 1774, and he had called the gas dephlogisticated air.) The same publication also introduced the French words that were soon adopted into English as hydrogen and sodium chloride (common salt), among other terms commonly used in chemistry. The French word oxygène was intended to mean "acid-producing," from the Greek word oxus, "sharp," used in the sense "acid," and the Greek suffix -genes, "born," misinterpreted as "producing." At the time oxygen was thought to be an essential component of an acid. Although this is not the case, the name oxygen has persisted for the element.
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Fourteen papers delivered at the March 2016 workshop present recent advances in understanding respiratory and photosynthetic electron transport chains, dynamic regulation of light harvesting, and electron transport events in oxygenic photosynthesis.
2] values would seem to indicate that these changes were probably caused by surface runoff during the rainy season, causing high turbidities, phytoplankton and phytobenthos shading and a consequent increase in oxygen demand accompanied by decreased oxygenic photosynthetic activity.
The only reason we have a well-oxygenated planet we can live on is because of oxygenic photosynthesis," Planavsky said.
Salinity stress also results in the generation of reactive oxygenic species (ROS) such as superoxide ([0.
2012) detected phylogenetic clustering of bacteria in deeper layers of the mat structure, while the clustering signal was lost in the top layers where oxygenic phototrophs including cyanobacteria reside.
Nash, 2005: The paleoproterozoic snowball Earth: A climate disaster triggered by the evolution of oxygenic photosynthesis.
Over-excitation is happening quite often: oxygenic organisms are exposed to (drastic) changes in environmental conditions (light intensity, light quality and temperature), which influence the physical (light-harvesting) and chemical (enzymatic reactions) parts of the photosynthetic process to a different extent, leading to severe imbalances.
However, in practice, it represents chlorophyll a, which is a widespread antenna pigment relative to other chlorophylls and is quantitatively the most predominant chloropigment produced by virtually all of the oxygenic photoautotrophs.
The carried out method try to transfer the recent lactate of the sample into the oxygenic water due to the effect of the oxidize lactate enzyme.
Chlorophyll modifications and their spectral extension in oxygenic photosynthesis.