Primary Sources of Reducing Equivalents
Organotrophs: Organic compounds are used as electron donor.
Lithotrophs: Inorganic compounds are used as electron donor.
The electrons from reducing equivalents are needed by both, phototrophs and chemotrophs, to keep running reduction-oxidation reactions that transfer energy. The electron donors are taken up from the environment.
Organotrophic organisms are often also heterotrophic, using organic compounds as sources of electrons and carbon at the same time. Similarly, lithotrophic organisms are often also autotrophic, using inorganic sources of electrons and CO2 as inorganic carbon source.
Some lithotrophic bacteria can utilize diverse sources of electrons, depending on availability of possible donors.
Read more about this topic: Primary Nutritional Groups
Famous quotes containing the words primary sources of, primary, sources and/or reducing:
“A fact is a proposition of which the verification by an appeal to the primary sources of our knowledge or to experience is direct and simple. A theory, on the other hand, if true, has all the characteristics of a fact except that its verification is possible only by indirect, remote, and difficult means.”
—Chauncey Wright (1830–1875)
“Wilful sterility is, from the standpoint of the nation, from the standpoint of the human race, the one sin for which the penalty is national death, race death; a sin for which there is no atonement.... No man, no woman, can shirk the primary duties of life, whether for love of ease and pleasure, or for any other cause, and retain his or her self-respect.”
—Theodore Roosevelt (1858–1919)
“On board ship there are many sources of joy of which the land knows nothing. You may flirt and dance at sixty; and if you are awkward in the turn of a valse, you may put it down to the motion of the ship. You need wear no gloves, and may drink your soda-and-brandy without being ashamed of it.”
—Anthony Trollope (1815–1882)
“It is the American vice, the democratic disease which expresses its tyranny by reducing everything unique to the level of the herd.”
—Henry Miller (1891–1980)