Aerobic respiration help!

[Chromeo33]

Could someone explain why some cells are able to produce 38 ATP molecules whilst some only produce 36 ATP molecules (during respiration)?

I read somewhere that it was "because NADH enters the respiratory chain earlier", but that just makes no sense to me at all..

Anyone care to elaborate?

[scocliffe09]

Could someone explain why some cells are able to produce 38 ATP molecules whilst some only produce 36 ATP molecules (during respiration)?

I read somewhere that it was "because NADH enters the respiratory chain earlier", but that just makes no sense to me at all..

Anyone care to elaborate?

It's more to do with the enzymatic pathways in the calvin cycle i think - but i'm not 100% sure.
What I do know is that it's unimportant, because in reality, cells very rarely even make 36 - because this is working at 100% efficiency - our uni lecturer suggested that 32 ATP was a more realistic number. So - don't fret about it. Just write 36-38 and be aware that neither is realistic!

[shinny]

Could someone explain why some cells are able to produce 38 ATP molecules whilst some only produce 36 ATP molecules (during respiration)?

I read somewhere that it was "because NADH enters the respiratory chain earlier", but that just makes no sense to me at all..

Anyone care to elaborate?

This was asked back in page 14 of the megaquestions thread where I said:

Not particularly VCE level knowledge, but it's because in the brain, liver, heart and kidneys, a certain shuttle molecule exists which doesn't elsewhere which brings the NADH made in glycolysis from the cytoplasm into the mitochondria so it can be reduced in the electron transport chain. Therefore you get more ATP. Keep in mind that these are all theoretical maximums. Apparently you get nowhere near 36-38 ATP.

[Russ]

If you actually care and want to read about it: http://en.wikipedia.org/wiki/Malate-aspartate_shuttle