AQA A2 Biol4 January 2012 pre- exam discussion

This isn't included in my book It simply states that as the electrons move down the chain of carriers sufficient energy is lost to phosphorylate ADP to ATP known as photophosphorylation Confused..

Ooh legacy papers
Haha I did this question too but didn't understand it too.

How's revision? Worried about this paper fml

Does anyone understand 7biii) of this paper: http://store.aqa.org.uk/qual/gceasa/qp-ms/AQA-BYB4-W-QP-JUN06.PDF ? I understand the order, just not exactly the explanation to go with it. Thanks

Wouldn't it be the obvious answer? ADP is used up when it combines with Pi to form ATP. Oxygen is the final electron acceptor in the electron transport chain, so is used up and so concentration decreases.

Does anyone understand 7biii) of this paper: http://store.aqa.org.uk/qual/gceasa/qp-ms/AQA-BYB4-W-QP-JUN06.PDF ? I understand the order, just not exactly the explanation to go with it. Thanks

Which textbook is that? The bit in bold was pretty important as it states how the ATP is synthesised.

Aha yeah there's not enough papers on the new spec.

Revision has been okayy, just getting so bored of it all. I can't wait till just under 3 weeks when they'll all be over! You?

well think about it in a step by step process.

Electron carriers become reduced when they receive electrons from the krebs cycle (and glycloysis). Enzymes catalyse the movement of the electrons from each electon carrier to the other. If an enzyme is inhibited all the molecules prior to that enzyme will be reduced (as they carry hold onto their electrons) and those after are oxidised. Thererfore, the carriers that are reduced with all the inhibitors will be first in the chain (and so on and so forth) until the last one which is always oxidised.

if you dont do a level chemistry and have forgotten gcse redox stuff- this question would probably be a lot harder.

Yep ( those papers are more nicer too IMO)
Yeah revisions okay, but it's really tedious. I hate ecology.
The exams hard too, but you're going to ace it like you always do ahah

just a question- is the old spec tests worth going through?

I guess I'll learn that then.. It's the A2 Nelson Thornes book! We haven't been taught this in lessons either

I haven't been taught this either, the A2 bio book seems to miss out a lot of details. I rely quite a lot on the specification too and it's not mentioned in there so i'll try to remember vaguely what happens there just in case

Woo that makes two of us I tried looking in the specification too but I can't seem to find it, I was trying to look for any past paper questions on the light dependent stage of photosynthesis to have a look in the mark scheme to see if they include it but I can't find any It doesn't seem like too much more to remember so hey ho

I can't find it either, but I suppose they could throw it in to confuse us For long mark questions there tends to be about nine points to choose from to make five or six marks, so it shouldn't be a big deal , unless they ask us about it specifically

The nelson thornes book does miss out chemiosmosis.

if you dont do a level chemistry and have forgotten gcse redox stuff- this question would probably be a lot harder.

Yeah hopefully we will be okay fingers crossed



It's supposedly "exclusively endorsed" by AQA.. Not sure what to make of that! Has anyone actually seen a question on chemiosmosis in any past papers?

Ooh, so hyrdogen gain/loss has nothing to do with being reduced or otherwise?

Eesh, nowonder I'm getting confused with the ETC ^^

OILRIG FTW