Alcohol Flashcards
Ethanol
The form of alcohol found in an alcoholic beverage.
ethanol is comprised of
two carbons and a single hydroxyl group
Alcohol Dehydrogenase (ADH)
The primary enzyme involved in metabolism of ethanol.
First-Pass Metabolism
The initial metabolism of ethanol occurring in the stomach, where a small amount of the ethanol in the beverage is immediately metabolized in the gastric mucosa (stomach lining) by alcohol dehydrogenase (ADH)
The majority of ethanol, however, passes unaltered into the bloodstream through the stomach and small intestine by ___________________________
simple diffusion
Once in circulation, the ____________________ allows it to diffuse into the majority of tissues, particularly the liver, due to the flow of blood directly from the stomach.
water solubility of ethanol
why does food slow the absorption of alcohol but increase the rate ethanol is metabolized?
it also increases the rate at which ethanol is metabolized, both by first-pass metabolism and metabolism in the liver, as a result of increased liver blood flow, activity of ADH, and rates of NADH, the reduced form of nicotinamide adenine dinucleotide (NAD+) re-oxidation
NADH provides the majority of electrons used for ATP production by ________________ within the mitochondria.
oxidative phosphorylation
males are ______% water
68%
females are ______% water
55%
Acetaldehyde
The toxic product of ethanol metabolism, which has to be further metabolized immediately to avoid its toxic effects.
Acetaldehyde Dehydrogenase
The enzyme used to metabolize toxic acetaldehyde.
Once in circulation, ____% of ethanol is metabolized in the liver by ADH at a rate of approximately _________ per hour.
90%,
0.25 (7 g) per hour
Metabolism of ethanol by ADH results in the formation of:
acetaldehyde and NADH
Acetaldehyde is toxic and is, therefore, metabolized rapidly and preferentially above other macronutrients to ____________ by the mitochondrial enzyme acetaldehyde dehydrogenase (ALDH2).
acetate
