Imagine that a lactate produced in a muscle cell enters the matrix of a mitochon
ID: 67057 • Letter: I
Question
Imagine that a lactate produced in a muscle cell enters the matrix of a mitochondrion via a transporter instead of leaving the cell and traveling to the liver to serve as a gluconeogenic precursor. Imagine further that once in the mitochondrial matrix of the muscle cell the lactate is oxidized by a nicotinamide-adenine-dinucleotide-dependent enzyme. How many ATPs could ultimately be made from this process if all the relevant mitochondrial machinery was put to use to make the maximum possible ATPs? Count any GTPs as ATPs.
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Explanation / Answer
Conversion of lactate to pyruvate produces one NADH, conversion of pyruvate to Acetyl-CoA produces one NADH and Krebs cycle produces 3 NADH, 2 FADH2 and one GTP.
In total 15 ATPs are produced (1NADH= 2.5 ATP, 1 FADH2= 1.5 ATP, 1 GTP= 1 ATP)