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    Can someone explain to me the difference between entrapment and membrane separation as methods of immobilising enzymes? The textbooks seem to list them as separate methods but they seem to be identical?

    ie
    Enzyme separated from substrate.
    Substrate diffuses through barrier.
    Enzyme catalyses reaction.
    Product diffuses out of barrier.

    There is no difference between entrapping/encapsulating enzymes using the membrane separation technique??
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    (Original post by phoebc)
    Hi guys i'm a bit confused and was wondering anyone could help
    To get an a* overall in the A2 units you need 270 UMS and on the OCR website it says students need to have 90% in all their A2 units
    but if someone got a high A in their A2 PSAs and then high A*s in their 2 exams so their UMS still added up to 270 would they be awarded an A* or an A?
    A*

    You need a total of 270/300 from the three units. It doesn't matter how you get to 270. So you could get 150/150 for f215, 60/60 for f216 and 60/90 for f214 and still get an a*

    :yes:

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    (Original post by The infamous Q.)
    A*

    You need 270/300. It doesn't matter how you get to 270. So you could get 150/150 for f215, 60/60 for f216 and 60/90 for f214 and still get an a*

    :yes:

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    so what does it mean when they say you need 90% in all A2 units?
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    (Original post by The infamous Q.)
    A*

    You need a total of 270/300 from the three units. It doesn't matter how you get to 270. So you could get 150/150 for f215, 60/60 for f216 and 60/90 for f214 and still get an a*

    :yes:

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    Bu thank u for response you have reassured me so much!
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    Hey guys this is an O level question. Cant find any help. Ans this question and explain thanks.

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    (Original post by phoebc)
    so what does it mean when they say you need 90% in all A2 units?
    Over all you need 90%, so 90% of the overall available A2 UMS, so 270/300 UMS. I don't know why this is so hard for everyone to get their heads around... Realistically, who's going to get all 90s?
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    Finally grasped photosynthesis especially the annoying experiments.
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    (Original post by AnnekaChan173)
    Over all you need 90%, so 90% of the overall available A2 UMS, so 270/300 UMS. I don't know why this is so hard for everyone to get their heads around... Realistically, who's going to get all 90s?
    Im on a gap year but mans got 57/60 on f216, 86/90 on f214 but 93/150 on f215.. :smug:

    Mans retaking dat f215

    Hopefully i'll get a* fam :yes::hand:

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    (Original post by phoebc)
    so what does it mean when they say you need 90% in all A2 units?
    Maybe it's some dodgy wording or something :hmmm:

    Ive always know that all u need for a* is 90% of the ums available at a2. Doesnt matter how you get them, just as long as you do

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    (Original post by The infamous Q.)
    Im on a gap year but mans got 57/60 on f216, 86/90 on f214 but 93/150 on f215.. :smug:

    Mans retaking dat f215

    Hopefully i'll get a* fam

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    Hard luck, you did well in the practicals and f214
    Good luck, and same here hopefully I'll get it too
    How's the gap year going?
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    The 2015 one is not out yet for obvious reasons
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    (Original post by The infamous Q.)
    Im on a gap year but mans got 57/60 on f216, 86/90 on f214 but 93/150 on f215.. :smug:

    Mans retaking dat f215

    Hopefully i'll get a* fam :yes::hand:

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    what happened on f215?
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    I have a photosynthesis one


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    (Original post by mollybryant82)
    ah ok thanks, that 'min' things sounds like another one of them over specific ocr stupid markschemes! yeah i will do and i've sent you a pm aswell! will be able to help you on the immobilsed enzymes one x
    Cheers! I've just emailed you! x
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    (Original post by Mnorth15)
    Cheers! I've just emailed you! x
    no problem! just emailed back! x
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    Hey can you pm me on immobilised enzymes to please

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    (Original post by Aneesah_May)
    Hey can you pm me on immobilised enzymes to please

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    yeah sure! i've just pm'd you x
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    Thank you

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    (Original post by phoebc)
    Did you specifically write phototaxis when you did the practical? because I only wrote specifically photokinesis. But I hope i've done well cause I did lots of revision for it and well done on 17/20 that's such a good mark I hope I got that because my eval marks is what is bring me down
    I can't actually remember exactly what I put, I think i put something about both kinesis and taxis aiding survival or something? I might just be imagining that though! Yeh I did quite a bit of revision as well so you should be fine, I hope you have. Thank you, I was so pleased and surprised! Its my second practical that has let me down so resitting that.
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    Has anyone done the evaluative on temperature of cells or enzymes something like that?
 
 
 
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