Bacteria don't do Krebs??

[doc3232]

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That's what Destroyer is saying. They don't do it in the mitochondria (because they don't have it), but still....

 

[yankees27th]

If Destroyer says it it must be true 😀

My guess is that the NADH produced from glycolysis only are used in the ETC.

 

[doc3232]

If Destroyer says it it must be true
😀
My guess is that the NADH produced from glycolysis only are used in the ETC.

I should put that in my signature...hahaha
But prokaryotes make same amount of ATP as eukaryotes (actually 2 more).
That would mean they still do Krebs right?

 

[MaskItOrCasket]

STOP STOP STOP!!!!

keep it simple...
1) destoryer is right... no krebs in prokaryotes, BUT they can still yield 38 ATP

in prokaryotes a net total of 38 molecules of ATP are produced by cellular respiration. Most prokaryotes have very simple cells which lack several types of organelles present in eukaryotes, and therefore the Krebs Cycle and the Electron Transport Chain occur in the cytoplasm and/or using chemicals embedded in the cell membrane. In contrast, eukaryotes have more complex cells with more specialized organelles to perform given functions. In eukaryotes, the Krebs Cycle and Electron Transport Chain occur within the mitochondria, and thus the pyruvic acid resulting from glycolysis must be sent into the mitochondria for these reactions to occur. However, to move one molecule of pyruvic acid (remember each molecule of glucose turns into two pyruvic acid molecules) from the cytoplasm into a mitochondrion "costs" the cell one molecule of ATP (therefore two ATPs for a whole glucose), thus a net total of 36 ATP molecules per molecule of glucose is produced in eukaryotes as compared to only two in fermentation.


2) NADH is used in other things than ETC besides oxidative phosphorylation

 

[doc3232]

STOP STOP STOP!!!!

keep it simple...
1) destoryer is right... no krebs in prokaryotes, BUT they can still yield 38 ATP

in prokaryotes a net total of 38 molecules of ATP are produced by cellular respiration. Most prokaryotes have very simple cells which lack several types of organelles present in eukaryotes, and therefore the Krebs Cycle and the Electron Transport Chain occur in the cytoplasm and/or using chemicals embedded in the cell membrane. In contrast, eukaryotes have more complex cells with more specialized organelles to perform given functions. In eukaryotes, the Krebs Cycle and Electron Transport Chain occur within the mitochondria, and thus the pyruvic acid resulting from glycolysis must be sent into the mitochondria for these reactions to occur. However, to move one molecule of pyruvic acid (remember each molecule of glucose turns into two pyruvic acid molecules) from the cytoplasm into a mitochondrion “costs” the cell one molecule of ATP (therefore two ATPs for a whole glucose), thus a net total of 36 ATP molecules per molecule of glucose is produced in eukaryotes as compared to only two in fermentation.


2) NADH is used in other things than ETC besides oxidative phosphorylation

I see, but then it has a Krebs-like cycle?

Also, Bio 133: RNA viruses are retroviruses. It is the other way around. All retroviruses are RNA viruses.

 

[MaskItOrCasket]

I see, but then it has a Krebs-like cycle?

Also, Bio 133: RNA viruses are retroviruses. It is the other way around. All retroviruses are RNA viruses.

yea all retroviruses are RNA viruses bc they need reverse transcriptase

 

[doc3232]

yea all retroviruses are RNA viruses bc they need reverse transcriptase

But some can use the RNA directly as mRNA. called something else: not retroviruses. Wiki called them something. These never use reverse transcriptase.

 

[JamesOSU]

MAn I'm glad the DAT is over. It's been 6 months and I completely forgot all this stuff, but I'm sure I did know it at one point ;-)

Good luck! Bio is definately the hardest to study for because the range of questions is hugggge

 

[Contach]

That's what Destroyer is saying. They don't do it in the mitochondria (because they don't have it), but still....

hmm.. Some bacteria will not be able to perform the Krebs cycle because they are anaerobic, thus don't need oxygen. We know that the Krebs cycle does need oxygen.

but I hear what you are saying about prokaryotes producing 2 more ATP than eukaryotes. But this must be in only a select few prokaryotes (those that are aerobic). It wouldn't make sense for them to have evolved the same mechanism of Krebs, so I'm thinking they can produce ATP in a similar way to Krebs, but not the same thing...

 

[rogerpc]

"In eukaryotic cells, the citric acid cycle occurs in the matrix of the mitochondrion. In prokaryotic cells, such as bacteria which lack mitochondria, the TCA reaction sequence is performed in the cytosol with the proton gradient for ATP production being across the cell's surface (plasma membrane) rather than the inner membrane of the mitochondrion."

https://en.wikipedia.org/wiki/Citric_acid_cycle

 

[DAT Destroyer]

That's what Destroyer is saying. They don't do it in the mitochondria (because they don't have it), but still....

For simplicity purposes no. There are some new species of bacteria that do Krebs cycle, but not in the mitochondria. Prokaryotes do not have mitochondria.