Is pyruvate decarboxylation usually considered part of the Krebs cycle?

[FROGGBUSTER]

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I got this question wrong cuz I kept them separate:

How much net ATP can be produced from the complete oxiDATion of a single molecule of glucose during glycolysis and the Krebs cycle? (Assume a yield of 3 ATP per NADH and 2 ATP per FADH2)
A. 0 ATP.
B. 3 ATP.
C. 28 ATP.
D. 38 ATP.
E. 40 ATP.

 

[reely989]

To me this is a terrible question, but given the way they asked it, I would probably assume they meant for you to keep them combined. I hate when they get into semantics about what is considered part of the krebs cycle, and then ignore that when actually asking the question.

I believe the answer should be 38. It says assume 3ATP/NADH which means you ignore the energy required to get the NADH's from Glycolysis into the mitochondria. But really, 38 is the only answer that makes sense. You only lose what, 6 ATP from leaving out decarboxylation? So, you'd end up with either 32 or 30 as an answer choice, neither of which is present.

 

[FutureDental88]

I got it to be C. 28.

Glycolysis gives 2; NADH.
Krebs cycle gives 6 NADH.
8 x 3 = 24

Krebs cycle gives 2 FADH2
2x2 = 4.

4+24 = 28.


Am i wrong?

 

[shdwpally]

Glycolysis = 2ATP + 2NADH
Pyruvate Dehydrogenase = 2NADH
Krebs cycle = 6NADH + 2FADH2 + 2GTP (ATP equivalent)

Total = 4ATP + 10NADH(3) + 2FADH2(2)
= 38 ATP

 

[FROGGBUSTER]

yeah hopefully there are none of these unclear questions on the actual exam.