Kinyonga
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I'm working on cellular respiration atm, but how much detail are we supposed to know for the exam? (I'm doing AQA.) Just what's listed here or all the detail that you can find on this image of the Krebs Cycle, for example?

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Jpw1097
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(Original post by Kinyonga)
I'm working on cellular respiration atm, but how much detail are we supposed to know for the exam? (I'm doing AQA.) Just what's listed here or all the detail that you can find on this image of the Krebs Cycle, for example?

Definitely nowhere near the level of detail on that image. The level of information you need to know is what it says on the specification. For A level, this is the level of detail that I knew:

In the link reaction, pyruvate (a 3 carbon molecule) is dehydrogenated and decarboxylated to acetyl-CoA (a 2 carbon molecule) by the pyruvate dehydrogenase complex. In this process, one molecule of CO2 . The dehydrogenation reaction transfers electrons (and H+) to NAD+ forming NADH. The decarboxylation removes the carboxyl group from pyruvate forming carbon dioxide.

Acetyl-CoA then enters the Krebs/citric acid/TCA cycle where it combines with oxaloacetate (a 4 carbon molecule) to form citrate (a 6 carbon molecule). The Krebs cycle is a series of dehydrogenation and decarboxylation reactions in which 2 CO2 molecules, 3 NADH, 1 FADH2, and one ATP (technically GTP but this is converted to ATP) are produced. At the end of one cycle, you are left with oxaloacetate again, which combines with another molecule of acetyl-CoA to form citrate, and the whole cycle goes round again. You do NOT need to know the names of all the intermediates and all the different enzymes. Just know the principles, decarboxylation reactions produced CO2, dehydrogenase reactions form either NADH or FADH2.

Hope that helps.
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Kinyonga
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(Original post by Jpw1097)
Definitely nowhere near the level of detail on that image. The level of information you need to know is what it says on the specification. For A level, this is the level of detail that I knew:

In the link reaction, pyruvate (a 3 carbon molecule) is dehydrogenated and decarboxylated to acetyl-CoA (a 2 carbon molecule) by the pyruvate dehydrogenase complex. In this process, one molecule of CO2 . The dehydrogenation reaction transfers electrons (and H+) to NAD+ forming NADH. The decarboxylation removes the carboxyl group from pyruvate forming carbon dioxide.

Acetyl-CoA then enters the Krebs/citric acid/TCA cycle where it combines with oxaloacetate (a 4 carbon molecule) to form citrate (a 6 carbon molecule). The Krebs cycle is a series of dehydrogenation and decarboxylation reactions in which 2 CO2 molecules, 3 NADH, 1 FADH2, and one ATP (technically GTP but this is converted to ATP) are produced. At the end of one cycle, you are left with oxaloacetate again, which combines with another molecule of acetyl-CoA to form citrate, and the whole cycle goes round again. You do NOT need to know the names of all the intermediates and all the different enzymes. Just know the principles, decarboxylation reactions produced CO2, dehydrogenase reactions form either NADH or FADH2.

Hope that helps.
That's very helfpul, thank you. I'll still go ahead and learn about the processes in more detail (it's so fascinating), but it's reassuring I don't have to memorise absolutely everything
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Jpw1097
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(Original post by Kinyonga)
That's very helfpul, thank you. I'll still go ahead and learn about the processes in more detail (it's so fascinating), but it's reassuring I don't have to memorise absolutely everything
Definitely go ahead and learn the process in more detail if you want. Never just stick to learning the spec, always try to understand why. The more detail you learn something, the easier facts (which are required at A level) will become much easier to remember. Even the level of detail I gave you is probably beyond what you need to know.
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