*Step 2 of cellular respiration
First: The 2 pyruvate molecules formed in glycolysis
are transported through the mitochondrial membranes
into the matrix.
Next: A multi-enzyme complex catalyzes 3 reactions:
1. A carboxyl group is removed by a decarboxylase
enzyme producing CO . (W2ich diffuses out of the
cell as waste).
2. Remaining 2-carbon portion is oxidized by NAD to
become acetic acid. NAD gains 2 hydrogen atoms
(from organic molecules of food) and becomes
NADH + H (NADH will be used later and H stays +