Alcohol Metabolism

Question 1

How much energy does ethyl alcohol or ethanol provide?

Answer 1

7 kcal/gram

Question 2

Where is alcohol primarily degraded?

Answer 2

It is oxidatively degraded in the liver

Question 3

The liver first converts ethanol to acetaldehyde and then to acetate. What do both of these steps produce?

Answer 3

NADH

Question 4

Ethanol oxidation is a three enzyme system. What are these enzymes?

Answer 4

• Alcohol dehydrogenase (ADH)
• MEOS (microsomal ethanol oxidizing system/cytochrome P-450 system)
• Catalase

Question 5

Where does alcohol dehydrogenase act?

Answer 5

Cytoplasm of liver cells

Question 6

When alcohol dehydrogenase is saturated, the “spill over” must be metabolized by what other system?

Answer 6

MEOS

Question 7

What cellular structure is MEOS associated with?

Answer 7

Endoplasmic reticulum

Question 8

Certain enzymes of MEOS are “inducible”, leading to hepatocytes being able to metabolize ethanol much more effectively. What is another name for this?

Answer 8

Tolerance

Question 9

What substance do both ADH and MEOS produce?

Answer 9

Acetaldehyde

Question 10

Oxidation of ethanol leads to the production of more NADH, which can influence other systems. Name some of these systems.

Answer 10

• Less fat burning
• TCA inhibition
• More fat synthesis
• More lactic acid