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  2. Evolution of photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_photosynthesis

    Oxygenic photosynthesis uses water as an electron donor, which is oxidized to molecular oxygen (O 2) in the photosynthetic reaction center. The biochemical capacity for oxygenic photosynthesis evolved in a common ancestor of extant cyanobacteria. [11] The first appearance of free oxygen in the atmosphere is sometimes referred to as the oxygen ...

  3. Jan Ingenhousz - Wikipedia

    en.wikipedia.org/wiki/Jan_Ingenhousz

    Jan Ingenhousz FRS (8 December 1730 – 7 September 1799) was a Dutch-British [1] physiologist, biologist and chemist.. He is best known for discovering photosynthesis by showing that light is essential to the process by which green plants absorb carbon dioxide and release oxygen.

  4. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    Photosynthesis usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen , cellulose and starches .

  5. Helium - Wikipedia

    en.wikipedia.org/wiki/Helium

    Helium is a commonly used carrier gas for gas chromatography. The age of rocks and minerals that contain uranium and thorium can be estimated by measuring the level of helium with a process known as helium dating. [28] [30] Helium at low temperatures is used in cryogenics and in certain cryogenic applications.

  6. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    In this layer ozone concentrations are about 2 to 8 parts per million, which is much higher than in the lower atmosphere but still very small compared to the main components of the atmosphere. It is mainly located in the lower portion of the stratosphere from about 15–35 km (9.3–21.7 mi; 49,000–115,000 ft), though the thickness varies ...

  7. Explainer-What is helium and why is it used in rockets? - AOL

    www.aol.com/news/explainer-helium-why-used...

    Helium also has a very low boiling point (-268.9°C or -452°F), allowing it to remain a gas even in super-cold environments, an important feature because many rocket fuels are stored in that ...

  8. Scientists confirm 'Earth-like' planet with atmosphere ... - AOL

    www.aol.com/news/2017-04-07-scientists-confirm...

    The discovery that GJ 1132b has an atmosphere is a key step in the search for life outside our solar system. Scientists confirm 'Earth-like' planet with atmosphere discovered 39 light-years from Earth

  9. Henry Cavendish - Wikipedia

    en.wikipedia.org/wiki/Henry_Cavendish

    Henry Cavendish FRS (/ ˈ k æ v ən d ɪ ʃ / KAV-ən-dish; 10 October 1731 – 24 February 1810) was an English experimental and theoretical chemist and physicist.He is noted for his discovery of hydrogen, which he termed "inflammable air". [1]