Cellular respiration question - please help!

[cdndds]

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Hey, so I have a question from one of the Kaplan practise tests:


One molecule of glucose is catabolized via cellular respiration. How many molecules of ATP are produced by oxidative phosphorylation?

a)2
b)4
c)34
d)36
e)40

Originally I thought the answer was D, but the book says C and here is the explanation:

C - 32 ATP are produced by the electron transport chain and oxidative phosphorylation. Ultimately, 1 molecule of glucose will be catalyzed to produce 36 ATP (32 from oxidative phosphorylation, 2 from the citric acid cycle, 2 from glycolysis).



What?? No idea where they are getting 34 out of this explanation... any help would greatly be appreciated!! Thanks!

 

[NDPitch]

It looks like they're including the 2 ATP that get produced in the Kreb's cycle?

Kind of a bogus question.

 

[ktran17]

This is dumb because they're assuming the organism is a prokaryote... thats why its 34 instead of 32..

since there is no mitochondria in prokaryotes the 2 NADH produced in glycolysis will yield 3ATP/NADH instead of 2ATP/NADH

Here's a chart for you to undestand what I'm saying =)

Eukaryote
Glycolysis
ATP invested -2 ATP
4 ATP generated +4 ATP (substrate)
2 NADH x 2 ATP/NADH +4 ATP (oxidative)
Pyruvate decarboxylation
2 NADH x 3 ATP/NADH +6 ATP (oxidative)
Kreb's cycle
6 NADH x 3 ATP/NADH +18 ATP (oxidative)
2 FADH2 x 2 ATP/FADH2 +4 ATP (oxidative)
2 GTP x 1 ATP/GTP +2 ATP (substrate)
Total +36 ATP

 

[jaymin8]

This is dumb because they're assuming the organism is a prokaryote... thats why its 34 instead of 32..

since there is no mitochondria in prokaryotes the 2 NADH produced in glycolysis will yield 3ATP/NADH instead of 2ATP/NADH

Here's a chart for you to undestand what I'm saying =)

Eukaryote
Glycolysis
ATP invested -2 ATP
4 ATP generated +4 ATP (substrate)
2 NADH x 2 ATP/NADH +4 ATP (oxidative)
Pyruvate decarboxylation
2 NADH x 3 ATP/NADH +6 ATP (oxidative)
Kreb's cycle
6 NADH x 3 ATP/NADH +18 ATP (oxidative)
2 FADH2 x 2 ATP/FADH2 +4 ATP (oxidative)
2 GTP x 1 ATP/GTP +2 ATP (substrate)
Total +36 ATP

Nevermind I got what you are saying.

 

[aqz]

The reason C was the best choice and D could not have been the right choice is because it asks for oxidative phosphorylation, which could be 32-34 ATP, but not 36.

36 ATP would be including the 4 ATP from substrate-level phosphorylation.

Still bogus nonetheless, but with some POE you can figure it out.