Glycolysis
is a biochemical pathway in which one six-carbon molecule of glucose is oxidized to produce two three-carbon molecules of
pyruvic acid. Glycolysis is an anaerobic (oxygen not needed) series of chemical reactions that are catalyzed by
specific enzymes. Glycolysis takes place in the cytosol of the cell.
At the beginning of the process 2 ATP are used to convert
one molcule of glucose into a new six-carbon molecule with two phosphate groups attached. This turns the two ATP into
two ADP. Next the two phosphate split the new carbon compound into two molecules of glyceraldehide 3 Phosphate
(G3P). Next up the two G3P become oxidized and they each receive a new phosphate group. This phosphate group comes
from the reduction of nicotine adenine dinucleotide (NAD+) to NADH. Recall that there are two G3P so everything desribed
at this point happens twice so there are now two NADH. Lastly the phosphate groups break from the G3P is given
to two ADP producing two ATP. There are two G3P so four ATP are produced in total. The two G3P molecules are then converted
into pyruvic acid. For every single glucose molecule used, there is net production of two ATP.
What happens to the pyruvic acid depends on the type
of cell and whether oxygen is present.
