Country: United States
Date: November 2007
How does the body make ATP energy from the oxygen?
Does the body generate ATP from oxygen? No, but all aerobic
organisms absolutely require oxygen for converting the chemical
energy found in food into a useful form. A cell in an organism
uses adenosine as the base for adding phosphate groups during
coupled catabolic reactions. For example, phosphate groups are
added to adenosine when breaking down a sugar in order to store
the bond energy of the sugar in a mono-, di-, or triphosphated
adenosine, i.e., AMP, ADP, or ATP. The adenosine base is used
repeatedly to store energy, as when AMP is used to generate ADP,
and when ADP is used to generate ATP via a cycle that adds phosphate
groups. The tri-phosphated adenosine is then dephosphorylated in
oupled anabolic reactions by which a cell generates macromolecules
that are encoded in the cell's DNA. It is the catabolic reactions
that require the oxygen to proceed. For example, look up the
chemistry that relates to the breakdown of the simple sugar
glucose. As you will find, the catabolic reaction will convert
the glucose to carbon dioxide, water, and energy. The energy is
largely captured in the coupled reaction that converts ADP to
Electrons from glucose are passed along the electron transport chain.
As the electrons are passed along, the energy inherent in the electrons
is released and used to synthesize
ATP from ADP + P. The final receptor of these electron is Oxygen which
combines with Hydrogen ions (H+) to form water.
Ron Baker, Ph.D.
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Update: June 2012