A2 Level - Question to do with Aerobic Respiration

My book states the following:
"The pyruvate molecules produced during glycolysis possess potential energy that can only be release using oxygen in a process called the during the Krebs Cycle"
But I thought the Krebs Cycle didn't feature oxygen?

Also, it states that the Krebs Cycle yields a large number of electrons.
Is this indirectly? I mean, electrons are donated from the reduced coenzymes which have formed as a result of the reduction of hydrogen carriers, which were produced in the Krebs Cycle.

What is oxidative phosporylation and where is this process involved?

Lookin' for simple answers :smile:

(edited 9 years ago)

Reply 1

MrPollockBiology

Oxidative phosphorylation is what happens on the electron transport chain.

Oxygen is required as the final electron acceptor to combine with H+ and e- to form water.

If there is no oxygen, the ETC stops, as electrons cannot move between carriers.

Because of this, reduced coenzymes cannot become oxidised at the start of the ETC.

Therefore, they can't go back to Link/Krebs to become reduced again.

Without O2; ETC, Krebs and Link stops, because NAD and FAD run out.

Reply 2

ps1265A

OP

14

Original post by MrPollockBiology

Oxidative phosphorylation is what happens on the electron transport chain.

Oxygen is required as the final electron acceptor to combine with H+ and e- to form water.

If there is no oxygen, the ETC stops, as electrons cannot move between carriers.

Because of this, reduced coenzymes cannot become oxidised at the start of the ETC.

Therefore, they can't go back to Link/Krebs to become reduced again.

Without O2; ETC, Krebs and Link stops, because NAD and FAD run out.

Thanks!

My book also says that without oxygen, glycolysis also stops. That is why 2 hydrogen atoms have to be given up to pyruvate to reform NAD. But what does this have to do with oxygen?

Reply 3

Hype en Ecosse

20

Original post by ps1265A

Thanks!

My book also says that without oxygen, glycolysis also stops. That is why 2 hydrogen atoms have to be given up to pyruvate to reform NAD. But what does this have to do with oxygen?

I think it might mean that respiration is stopped AT GLYCOLYSIS. The 2 hydrogen ions usually go on and get given to oxygen (at oxidative phosphorylation), but since that can't occur (due to lack of oxygen!) they get plugged on to pyruvic acid to form lactic acid. :smile:

Posted from TSR Mobile

A2 Level - Question to do with Aerobic Respiration

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you