chemotroph
Quick Summary
A chemotroph is an organism that obtains energy by oxidizing inorganic or organic compounds. This is in contrast to phototrophs, which derive energy from light. Chemoautotrophs specifically use inorganic compounds as their energy source and carbon dioxide as their carbon source. Examples include bacteria that oxidize ammonia, methane, or hydrogen sulfide. Chemoheterotrophs, on the other hand, use organic compounds for both energy and carbon. Organisms that perform chemoautotrophy are crucial primary producers in ecosystems where sunlight is unavailable, such as deep-sea hydrothermal vents.123456
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marine ecosystemOrganisms of the deep-sea vents…organisms are referred to as chemoautotrophic, or chemosynthetic, as opposed to photosynthetic, organisms. Many of the species in the vent fauna have developed symbiotic relationships with chemoautotrophic bacteria, and as a consequence the megafauna are principally responsible for the primary production in the vent assemblage. The situation is analogous to…
Read More…organisms are referred to as chemoautotrophic, or chemosynthetic, as opposed to photosynthetic, organisms. Many of the species in the vent fauna have developed symbiotic relationships with chemoautotrophic bacteria, and as a consequence the megafauna are principally responsible for the primary production in the vent assemblage. The situation is analogous to…
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trophic pyramidThe base of the pyramidSulfur-oxidizing bacteria (chemoautotrophs) thrive in the warm, sulfur-rich water surrounding these cracks. The bacteria use reduced sulfur as an energy source for the fixation of carbon dioxide. Unlike all other known biological communities on Earth, the energy that forms the base of these deep-sea communities comes from…
Read MoreSulfur-oxidizing bacteria (chemoautotrophs) thrive in the warm, sulfur-rich water surrounding these cracks. The bacteria use reduced sulfur as an energy source for the fixation of carbon dioxide. Unlike all other known biological communities on Earth, the energy that forms the base of these deep-sea communities comes from…
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lifeThermodynamic…deep-sea and cave organisms called chemoautotrophs depend on chemical gradients, such as the natural energy-producing reaction between hydrogen sulfide bubbling up from vents and oxygen dissolved in water. The organization of life on Earth can thus be seen as being driven by a natural second-law-based reduction between the energy of…
Read More…deep-sea and cave organisms called chemoautotrophs depend on chemical gradients, such as the natural energy-producing reaction between hydrogen sulfide bubbling up from vents and oxygen dissolved in water. The organization of life on Earth can thus be seen as being driven by a natural second-law-based reduction between the energy of…
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lifeEnergy, carbon, and electrons…from oxidative chemical reactions (chemoautotrophs). The latter mode of metabolism refers to life-forms that use inorganic materials (ammonia [NH3], methane [CH4], or hydrogen sulfide [H2S]) combined with oxygen to generate their energy. Only some bacteria are capable of obtaining energy by “burning” inorganic chemicals.
Read More…from oxidative chemical reactions (chemoautotrophs). The latter mode of metabolism refers to life-forms that use inorganic materials (ammonia [NH3], methane [CH4], or hydrogen sulfide [H2S]) combined with oxygen to generate their energy. Only some bacteria are capable of obtaining energy by “burning” inorganic chemicals.
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lifeEnergy, carbon, and electrons…transformations to be available to chemoautotrophs and heterotrophs over sustained periods of time, ecological cycles are required. For geologically short periods of time, organisms may live off a finite supply of material; however, for any long-term continuance of life, a dynamic cycling of matter involving complementary types of organisms must…
Read More…transformations to be available to chemoautotrophs and heterotrophs over sustained periods of time, ecological cycles are required. For geologically short periods of time, organisms may live off a finite supply of material; however, for any long-term continuance of life, a dynamic cycling of matter involving complementary types of organisms must…
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lifeTemperature and desiccationOthers sustain themselves by their chemoautotrophic bacterial associations.
Read MoreOthers sustain themselves by their chemoautotrophic bacterial associations.
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lifeGeologic record…internal microbial symbionts (photo- or chemoautotrophs) for nourishment. No evidence that they were animals exists. In addition to the Ediacarans, acritarchs, and other abundant microfossils, clear evidence for pre-Phanerozoic, or Precambrian, life includes the massive banded-iron formations (BIFs). Most BIFs date from 2.5 billion to 1.8 billion years ago. They…
Read More…internal microbial symbionts (photo- or chemoautotrophs) for nourishment. No evidence that they were animals exists. In addition to the Ediacarans, acritarchs, and other abundant microfossils, clear evidence for pre-Phanerozoic, or Precambrian, life includes the massive banded-iron formations (BIFs). Most BIFs date from 2.5 billion to 1.8 billion years ago. They…
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