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metabolic diversity
mesotrophic ~eutrophic regions.
Mesozoa small marine phylum of small, ciliated, multicellular parasites. They
can be endoparasites of Turbellaria, Nemertina, Annelida, Bivalvia, Cephalopoda and
Echinodermata. The larvae or the sexual stage can be free-living. Their very
primitive appearance is probably secondary, and a result of parasitic adaptation.
Mesozoic ~geological time scale.
Messinian ~salinity crisis.
metabiosis cooperation of different organisms to degrade substances, e.g.,
refractory substances such as lignin or cellulose. These are first attacked by
specialist microorganisms possessing enzyme systems for the decomposition of such substances and after that other microbes that can utilize the
intermediate products follow. Thus the first create the pre-conditions for the
development of the latter group of organisms, by whose activities an accumulation of harmful metabolic products is avoided. This kind of cooperation is widespread in nature.
metabolic diversity the overwhelming amount of morphologically different
types of living organisms shows a remarkable unity in their biochemistry.
Also in the metabolic processes of evolutionary different groups of organisms an impressive diversity exists. Especially among microorganisms a
large variety of metabolic types can be found. On the basis of the energy
source or the carbon sources used, organisms can be divided into various
categories. If the energy source is chemical the organisms are chemotrophs. If
they use light as energy source they are phototrophs. The chemotrophs can be
divided into organisms that use the energy from reduced inorganic compounds (hydrogen, reduced S-compounds, reduced N-compounds, reduced
Fe, or reduced Mn) the (chemo)lithotrophs and organisms that use the energy
from organic matter the (chemo)organotrophs. The generation of energy must
be separated clearly from the carbon source they use for building their biomass. If organisms use carbon dioxide as C-source they are autotrophs and if
they use organic matter as C-source they are heterotrophs. So chemoorganotrophs are always heterotroph. But organisms such as the sulfate-reducing
bacteria that use hydrogen as energy source and organic matter as C-source
belong to the category chemolithoheterotrophs. The hydrogen bacteria using
hydrogen as energy source and carbon dioxide as C-source belong to the
chemolithoautotrophs. Phototrophs are mostly autotroph (photolithotrophs or
photoautotrophs) but if they use organic matter as C-source they belong to
the photoorganotrophs or photoheterotrophs. Metabolic diversity exists also in
the way of oxidizing reduced inorganic or organic matter. The electron
metabolic diversity
mesotrophic ~eutrophic regions.
Mesozoa small marine phylum of small, ciliated, multicellular parasites. They
can be endoparasites of Turbellaria, Nemertina, Annelida, Bivalvia, Cephalopoda and
Echinodermata. The larvae or the sexual stage can be free-living. Their very
primitive appearance is probably secondary, and a result of parasitic adaptation.
Mesozoic ~geological time scale.
Messinian ~salinity crisis.
metabiosis cooperation of different organisms to degrade substances, e.g.,
refractory substances such as lignin or cellulose. These are first attacked by
specialist microorganisms possessing enzyme systems for the decomposition of such substances and after that other microbes that can utilize the
intermediate products follow. Thus the first create the pre-conditions for the
development of the latter group of organisms, by whose activities an accumulation of harmful metabolic products is avoided. This kind of cooperation is widespread in nature.
metabolic diversity the overwhelming amount of morphologically different
types of living organisms shows a remarkable unity in their biochemistry.
Also in the metabolic processes of evolutionary different groups of organisms an impressive diversity exists. Especially among microorganisms a
large variety of metabolic types can be found. On the basis of the energy
source or the carbon sources used, organisms can be divided into various
categories. If the energy source is chemical the organisms are chemotrophs. If
they use light as energy source they are phototrophs. The chemotrophs can be
divided into organisms that use the energy from reduced inorganic compounds (hydrogen, reduced S-compounds, reduced N-compounds, reduced
Fe, or reduced Mn) the (chemo)lithotrophs and organisms that use the energy
from organic matter the (chemo)organotrophs. The generation of energy must
be separated clearly from the carbon source they use for building their biomass. If organisms use carbon dioxide as C-source they are autotrophs and if
they use organic matter as C-source they are heterotrophs. So chemoorganotrophs are always heterotroph. But organisms such as the sulfate-reducing
bacteria that use hydrogen as energy source and organic matter as C-source
belong to the category chemolithoheterotrophs. The hydrogen bacteria using
hydrogen as energy source and carbon dioxide as C-source belong to the
chemolithoautotrophs. Phototrophs are mostly autotroph (photolithotrophs or
photoautotrophs) but if they use organic matter as C-source they belong to
the photoorganotrophs or photoheterotrophs. Metabolic diversity exists also in
the way of oxidizing reduced inorganic or organic matter. The electron