Two Possible Pathways
- If there is no oxygen present (anaerobic) the pyruvic acid
is converted to lactic acid and there is no further production
of ATP
- Large amounts of lactic acid in muscle leads to fatigue and
can cause cramps. There are no legal ways to prevent lactic acid
build up (there are illegal buffers which counteract the acidity
of the lactate).
- If there is oxygen present (aerobic) the pyruvic acid is
broken down into two molecules of carbon dioxide, four atoms
of hydrogen and two molecules of acetyl-coenzyme A (a two carbon
compound)
- The four atoms of hydrogen go into the hydrogen carrier system
where six additional ATPs are produced
- The two molecules of acetyl-coenzyme A molecules go into
the Krebs or Citric Acid Cycle
which yields even more ATP