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AQA Biology AS New Spec - 26th May and 7th June Watch

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    (Original post by CrazyFool229)
    But taking a larger measurement (which lowers the percentage uncertainty of a measurement) is different to using a larger unit.

    Say I had a book that I measured as 10mm using a mm ruler

    Converting it to 1cm isn't going to make that measurement anymore accurate.

    i.e 1cm is larger than 1mm therefore mm is more accurate.

    A cm is 0.01m
    A mm is 0.001m
    Actually using cm^2 is taking a larger measurement because its 100x larger than a mm^2, you're not measuring the size of something you're measuring the frequency in a given space, so cm^2 is absolutely taking a larger measurement
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    (Original post by Splaffie)
    Actually using cm^2 is taking a larger measurement because its 100x larger than a mm^2
    No it isn't.

    If I measured the distance from my house to my neighbour's door as 100cm
    and then I measured it again using a millimeter ruler which means the result is 1000mm

    They are the SAME size. Taking a measurement using cm doesn't suddenly make the distance between my house and my neighbour's door does it?
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    (Original post by GabbytheGreek_48)
    that was my reaction too but doesnt the microscope produce a 2d image in this case so wouldnt it be cm2?
    oh yeah i put cm2
    i didn't read the post i replied to properly haha
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    (Original post by cat_fish)
    What did you guys put for the mean species richness and oxygen dissociation curve?
    mean richness was 14 or 13 something like that and the dissociation curve was that haemoglobin has higher affinity for oxygen
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    (Original post by Splaffie)
    Pretty sure it's cm squared because it has a higher precision than mm squared and m squared is impractical
    It would be very difficult for the student to count all the stomata per cm2 don't you think? mm2 sounds way more practical considering there will be hundreds of stomata in a cm2
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    (Original post by GabbytheGreek_48)
    frame shift and change in amino acid and tertiary structure is a deletion so that should be right
    Any question like that its always the same marks

    1) Change in base sequence
    2) Change in primary structure
    3) Change in position of hydrogen, ionic, disulphide bonds
    4) Therefore a change in tertiary structure
    5) So no longer complementary to the HIV antigen
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    (Original post by Namita Gurung)
    I crammed the translocation thing this morning as well :lol: Was so happy when it came up.
    same if you scroll back i explained translocation because i knew they were gonna put it in the exam - aqa are horrible people
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    (Original post by neyscar)
    Yeah that's what I wrote.
    ah so the second mark was the large sa:v i was thinking of writing that never did it
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    (Original post by Why-_-Study-_-)
    Attachment 544397

    Mass transport Hypothesis

    Active transport is used to actively load solutes ( such as sucrose ) from companion cells into the sieve tubes of the phloem at the source.
    This - Lowers the water potential inside the sieve tubes so water enters the tubes by osmosis via the Xylem vessels and companion cells
    - creating high pressure inside the sieve tube elements at the source end

    At the sink end, solutes are removed from the phloem to be used.
    This - Increases water potential inside the sieve tubes, which means water leaves the sieve tubes by osmosis
    - thus lowering the pressure inside the sieve tubes

    This Pressure Gradient from the source end to the sink end pushes solutes along the sieve tubes towards the sink - where they are used up ( in respiration or stored as starch)


    I am pretty sure i got full marks on this
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    (Original post by lilyjacks)
    dipeptidase
    Got that question so wrong xD
    It was the first one as well, now I'm dreading what my results for Bio are going to be
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    guys do you think on average 68% on both papers will be an A??

    That means 51 and 51 on both papers
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    (Original post by Mr PB)
    guys do you think on average 68% on both papers will be an A??

    That means 51 and 51 on both papers
    68% seems a bit low... I'm guessing 75% average for both for an A?

    I have no idea though, generally I go by 80% for an A, 70% for a B, 60% for a C but because it's a new spec maybe -5% for them? I don't think the papers were all that difficult especially paper 2.
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    No because if you look at previous years its never been 80% and when the previous spec came out in 2009 it was on average 65.6%
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    (Original post by Senthil Patel)
    Any question like that its always the same marks

    1) Change in base sequence
    2) Change in primary structure
    3) Change in position of hydrogen, ionic, disulphide bonds
    4) Therefore a change in tertiary structure
    5) So no longer complementary to the HIV antigen

    What other measurement was needed for species diversity index? And what 2 things needed to be controlled anyone???
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    You needed to know the number of organisms within each individual species
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    (Original post by Luchamb)
    What other measurement was needed for species diversity index? And what 2 things needed to be controlled anyone???
    Number of organisms in each species of beetle

    (Original post by Mr PB)
    No because if you look at previous years its never been 80% and when the previous spec came out in 2009 it was on average 65.6%
    Wow were they really that low? My teacher always went by 80% at least for an A in our school for our mocks, probably to make us revise more lol. Anyway if it is 65% then that would be bloody brilliant.
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    (Original post by CrazyFool229)
    Number of organisms in each species of beetle



    Wow were they really that low? My teacher always went by 80% at least for an A in our school for our mocks, probably to make us revise more lol. Anyway if it is 65% then that would be bloody brilliant.
    Yh the maximum they've been is 78% and this was an anomalous result as before this one it was 72% max
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    (Original post by CrazyFool229)
    Number of organisms in each species of beetle
    Yass I wrote this as well.

    Didn't revise the formula as well as the other bio topics so just used common sense.

    Completely messed up on the dipeptidase one - wrote down protease e.g. amylase instead.
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    (Original post by Namita Gurung)
    Yass I wrote this as well.

    Didn't revise the formula as well as the other bio topics so just used common sense.

    Completely messed up on the dipeptidase one - wrote down protease e.g. amylase instead.
    Don't worry - A LOT of people in our school put protease/other answers for the first question. It baffled me at first so I had to go back to it right at the end.
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    still have not done paper 1 or paper 2

    what topics come up in paper 1?
 
 
 
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