In the first stage of alcohol metabolism ADH catalyzes the conversion of alcohol to Choose...acetyl CoAacetateacetaldehydealdehyde dehydrogenase. As much as 20% of alcohol is changed to that substance in Choose...the mouththe stomachthe digestive tractthe liver. The metabolic reactions that convert alcohol to the above consume NAD+ while forming NADH. The resulting build up dramatically slows the citric acid cycle. As a result cells route most of the acetyl CoA to the synthesis of Choose...amino acidsfatty acidsacetateketone bodies.

As alcohol builds up in the body, the body recognizes it as foreign and routes it into the primary overflow pathway called the Choose...MEOSMSOSEMSSMESO. The Choose...pancreaskidneyssmall intestineliver ordinarily uses this system to metabolize drugs and detoxify foreign substances. When exposed to large doses of alcohol repeatedly this pathway’s capacity and speed increase.