Autotrophic Organisms

Autotrophic Organisms

 

organisms that synthesize the organic substances necessary for life from inorganic materials. The role of autotrophic organisms in nature is enormous, since they create all organic matter, which cannot be synthesized by man and almost all animals. Higher plants (excluding parasites and saphrophytes), algae, and some bacteria are autotrophic organisms. Higher plants and algae contain chlorophyll and are photosynthetic; they synthesize organic substances from simple compounds—carbon dioxide gas and water—using solar energy.

Autotrophic bacteria are chemosynthetic; they synthesize organic matter from mineral compounds, utilizing the energy of certain chemical reactions. For example, the soil bacteria Nitrosomonas and Nitrobacter oxidize ammonia to nitrates and nitrites and use the resulting energy in body building; ferrobacteria use the oxidation energy of ferrous forms of iron; sulfur bacteria oxidize hydrogen sulfide to the sulfuric acid salt (some species of sulfur bacteria are colorless and are typically chemosynthetic; others—for example, the purple sulfur bacteria—are colored and are capable of photoreduction, photosynthesis in which the hydrogen source for reduction of carbon dioxide gas is not water but hydrogen sulfide). Autotrophic organisms play an extremely large role in the circulation of matter in nature.

REFERENCE

Vernadskii, V. I. “Zhivoe veshchestvo pervogo i vtorogo poriadka v biosfere.” lzbr. soch., vol. 5. Moscow, 1960. Pages 63–71.
References in periodicals archive ?
As such it is the core network for ecological biochemistry as well as for autotrophic organisms since all large-scale ecological systems go through an autotrophic primary trophic level.
Star anise, star aniseed, or Shikimic acid, a primary feedstock used to create the anti-flu drug Tamiflu, is produced by most autotrophic organisms, but star anise is the industrial source.
Strictly autotrophic organisms were related to members of the genera Thioclava, Thiomicrospira, and Halothiobacillus, whereas facultative autotrophs were related to the genera Halomonas and Salinisphaera.
Phytoplankton consists of unicellular autotrophic organisms and also includes others that are clearly derived directly from autotrophic organisms, even if they are clearly totally or partially heterotrophic.
Within marine trophic chains, zooplankton constitute the step that channels the energy produced by autotrophic organisms to the secondary consumers.
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms.
The rTCA cycle shown in Figure 1 is the core of synthesis in autotrophic organisms and supplies source compounds for the building blocks that undergo condensation and polymerization reactions to yield macromolecules.
It is noteworthy, however, that heterotrophic biomass (mainly bacteria) surpassed several times the biomass of autotrophic organisms, being the largest contributor to the total biomass <20 [micro]m in the photic layer of both stations in Southern Cuban oceanic waters.