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    This thread is making me sad
    PLEASE low grade boundaries!!
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    (Original post by FatalError)
    But directional selection is a shift of the mean which isn't the case here?
    Well potentially there would be a slight shift in the mean in terms of percentage with the normal genotype. Since there would be less with the recessive genotype, a greater percentage would be normal so it could be argued the mean has changed.
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    (Original post by Scarface-Don)
    I dont think is directional, its stabilising because only a small proportion of the population had the recessive allele that did not produce the enzyme, and these individuals will have a disadvantage so their unlikely to pass on their alleles. Thus the selection favours the average individual of the population that does produce the enzyme. If the recessive allele was beneficial then it may have been directional.

    (Original post by andrewcreed)
    It's directional selection. In stabilising selection both extremes are acted against, which is not the case here. In directional selection, only one extreme is acted against, which is the case. I can see the arguments people have for stabilising but I'm certain they will want directional for the answer.
    It's definitely directional selection, because from a similar question in a previous paper, the reasoning behind it was "the populations characteristics are being changed not preserved"
    and that is what is happening here..
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    Mm it's 3 marks right?
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    (Original post by Rainbow249)
    Aww bless you, you'll be fine! I think the grade boundaries will be low enough for you to get an A

    I'm doing Pharmacy, so we're doing similar courses hahahaa! This ur first exam?
    where you doing pharmacy at?
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    But it is being preserved in the fact that the allele frequency is higher for T and that is what is being preserved.
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    (Original post by FatalError)
    Mm it's 3 marks right?
    It was only 2. One for determining which type of selection and one for the explanation. Nothing too major.
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    maybe it could be either directional or stabilising as long as your justify it? i hope so haa
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    The question about oil gland sizes and no. mites, what did people put for the relationship? I put there was very weak correlation/not much correlation, because all the points lie far from the line of best fit/scattered..
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    (Original post by Rickesh)
    I got 4% for the hardy weinburg too ! What did everyone put for the question following that about what they hardy weinburg predicts will happen to the t allele or something like that??
    that is predicts that the proportion of t to T is the same over generations
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    (Original post by andrewcreed)
    It's directional selection. In stabilising selection both extremes are acted against, which is not the case here. In directional selection, only one extreme is acted against, which is the case. I can see the arguments people have for stabilising but I'm certain they will want directional for the answer.
    Its a debatable question.
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    (Original post by MessyRoom)
    I think it would decrease reliability, measuring the area in which the mites lived could disturb the habitat and remove some from the area. Doing so would make the results unreliable.

    at the beginning of the question it said something along the lines of....after preening the gland gets smaller.....
    Don't know if the reliability has something to do with that?
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    (Original post by supernova92)
    It's definitely directional selection, because from a similar question in a previous paper, the reasoning behind it was "the populations characteristics are being changed not preserved"
    and that is what is happening here..
    Could you link me to that paper please.
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    (Original post by tehsponge)
    I know. I feel awful right now. I don't want to go to my Insurance choice, and the fees rise next year... Looks like I'll be going through Clearing.
    Don't think negative. Just get off this thread haha. Focus on your next exam. I'm sure you will be fine
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    (Original post by Betsss)
    The question about oil gland sizes and no. mites, what did people put for the relationship? I put there was very weak correlation/not much correlation, because all the points lie far from the line of best fit/scattered..
    I put there was a slight positive correlation but that it was hard to prove any relationship because many had no change in number of mites despite varying oil gland sizes and there was also a lot of variation. So basically the data was pretty inconclusive.
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    OP, please could you make a poll for this thread asking how everyone found the paper. Thanks
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    (Original post by FatalError)
    But it is being preserved in the fact that the allele frequency is higher for T and that is what is being preserved.

    (Original post by andrewcreed)
    It is acting in the direction favouring the normal genotype and therefore is directional. I can see your argument - it isn't a very good question but I'm pretty sure the mark scheme will be looking for directional.

    (Original post by supernova92)
    It's definitely directional selection, because from a similar question in a previous paper, the reasoning behind it was "the populations characteristics are being changed not preserved"
    and that is what is happening here..
    OMG mAYBE THE ANSWER IS NATURAL SELECTION.

    COZ its survival of the fittest and both directional and stabilising are both wrong.
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    Can someone list all the questions and what they were generally about?
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    for the question about why actual number was different from expected number would chance be a valid answer?
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    (Original post by Ruksha)
    for the question about why actual number was different from expected number would chance be a valid answer?
    Yes I put down it was due to probability and the most likely occurances.
 
 
 
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