A2 Biology OCR June 2015 Revision Thread

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Reply 1100

BioAgent

F215 is really boring :frown:

Reply 1101

maisie__x

Original post by baffledchick

what are the ums scores overall for each grade for the whole a level?

a = 480 b=420 c=360 d=300 e =240

Reply 1102

Telos

Original post by medactuary

If you limit light intensity - what happens to the amount of TP in the calvin cycle?

RuBP decreases (TP isn't converted to RuBP)
GP increases (as remaining RuBP is still carboxylated)

So TP accumulates? Even though GP can't be converted to TP?

Lower light intensity so less ATP & reduced NADP produced in light-dependent stage.
But ATP and reduced NADP are required to convert GP to TP, so less GP can be converted to TP. Therefore GP concentration increases, while the concentration of TP decreases
RuBP is still being converted into GP (and less TP being converted to RuBP) so RuBP concentration decreases.

(edited 8 years ago)

Reply 1103

baffledchick

Original post by maisie__x

a = 480 b=420 c=360 d=300 e =240

Thank you! Trying to see what I need overall, I have 212 UMS at AS, I think achieving an A is now impossible

Reply 1104

maisie__x

Original post by baffledchick

Thank you! Trying to see what I need overall, I have 212 UMS at AS, I think achieving an A is now impossible

Remember to add your A2 coursework to that as well? :smile:

You could achieve an A but you'd probably need nearly full UMS in both exams this year

Reply 1105

baffledchick

Original post by maisie__x

Remember to add your A2 coursework to that as well? :smile:

You could achieve an A but you'd probably need nearly full UMS in both exams this year

I'm really annoyed I messed up my BIO 2 retake, I might have to settle for the B, full UMS in unit 5 is looking like a myth. Thanks :smile:

thanks!

In Light independent reaction , how many TP are produced in 1 turn of the cycle? is it 1tp or 2 tp's?

Reply 1108

Qui

Predictions for unit 4 and 5?

Reply 1109

AnnekaChan173

Original post by Beni24

In Light independent reaction , how many TP are produced in 1 turn of the cycle? is it 1tp or 2 tp's?

2x TP are made every turn of the cycle.

I haven't looked at Unit 5, am I screwed? :/

Reply 1110

catrionaw

Does anyone have any predictions of which topics may come up?

Reply 1111

maisie__x

Original post by AnnekaChan173

2x TP are made every turn of the cycle.

I haven't looked at Unit 5, am I screwed? :/

You're not screwed! In my opinion whilst F215 is boring and there's a lot to learn, it's a lot easier and some of the topics, like animal/plant responses, are really small and quick to learn. Obviously the best grades come from doing past papers and learning absolutely everything, but I still think you can get a decent enough grade on F215 by skimming over some things. Some of the questions on past papers seem like common sense, advantages and disadvantages of things :smile:

(that being said look over the ecosystems topic if nothing else, there's always loads on that)

Reply 1112

ChoccyPhilly

Original post by Beni24

In Light independent reaction , how many TP are produced in 1 turn of the cycle? is it 1tp or 2 tp's?

You start with RUBP (5c), carbon fixation into an intermediate compound (6C) before breaking down into Gylcerate-3-phosphate (2x3C), which is converted into TP (2x3C)

Original post by AnnekaChan173

2x TP are made every turn of the cycle.

I haven't looked at Unit 5, am I screwed? :/

Wow, you seemed better prepared than most of us in this thread. I don't know how you're spreading yourself for the other subjects but if you allocate maybe 2-4 hours a day solely on unit 5, you could very well set yourself up for a good grade in a fortnight

Reply 1113

ChoccyPhilly

Original post by BioAgent

F215 is really boring :frown:

Ranked most interesting to most boring imo:

Unit 5
Unit 4
Unit 1
Unit 2

I really didn't like the classification/biodiversity/ecology/evolution chapters. At least in unit 5 we do some better ecology like the nitrogen cycle

Reply 1114

Beni24

Original post by AnnekaChan173

2x TP are made every turn of the cycle.

I haven't looked at Unit 5, am I screwed? :/

Thank you! :smile:

This is unit 4, but yeah dont worry I havent even looked at unit 5 yet haha Im just going to concentrate on unit 4 :smile:

Reply 1115

BioAgent

Original post by ChoccyPhilly

I suppose If you like general biology then unit 5 is more your thing but I like human biology especially physiology stuff so I found 4 and 1 to be most interesting.

Reply 1116

Octarine_Flame

Original post by Shostakovish

Difference between Lamellae and Thylakoids?

Further to my previous response, if in the exam they asked us to label a lamella in the chloroplast, I think it's best to label an intergranal lamella (the extension of the thylakoid membrane which connects two grana).

:smile:

Reply 1117

baffledchick

What synoptic stuff comes up in unit 4?

Reply 1118

Beni24

Has anyone done January 2013 paper for F214? Can someone please explain how they got percentage answer? i dont understand :?

Reply 1119

YouAgain

Original post by Bethanwhitexx

has anyone got any slight predictions for F214 my teacher is crap and I have received no guide on what to focus a lot on!! so stuffed for this exam :frown: