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    (Original post by PlayerBB)
    I'm gonna start solving p.p tmw, u?
    hey
    same here... omg they r like literally empty but if ive made a good schedule and ill finish by 30th
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    (Original post by AJC1997)
    yeah, I was also thinking about maybe mentioning prenatal testing BUT the question already said that both parents
    were carriers - as they were heterozygous, meaning testing and amniocentesis would have no benefit as they already knew that they were at risk of giving birth to a sufferer.
    Yes true,you have a point....So it's alright if I mentioned about 25% risk and drew the punnet box and yeah that's it I guess for that question.
    Also what did you write for the risk associated with the use of heparin,is liver damage alright?
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    (Original post by A84)
    hey
    same here... omg they r like literally empty but if ive made a good schedule and ill finish by 30th
    Hahahahah same

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    (Original post by Polpi)
    Yes true,you have a point....So it's alright if I mentioned about 25% risk and drew the punnet box and yeah that's it I guess for that question.
    Also what did you write for the risk associated with the use of heparin,is liver damage alright?
    I just said excessive bleeding if they get injured + liver damage is right too
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    (Original post by AJC1997)
    Well it's reassuring to here I didn't write complete rubbish for this question, I'm happy with 3+ marks for it haha
    Most of the pounts match except for the fact that i wrote that the potatoes to be cooked in a range of temperatures for the same amount of time since it was asked "the effect of cooking" not time or any temperature in particular..
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    (Original post by Lama1847)
    what did u write for why galactose and glucose are monosaccharides
    both have a general formula of C6H12O6 and are the simplest molecules that have not undergone a condensation reaction :/ Not so sure if it's right
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    (Original post by AvWOW)
    both have a general formula of C6H12O6 and are the simplest molecules that have not undergone a condensation reaction :/ Not so sure if it's right
    I wrote since both of them are composed of single units and are made of carbohydrates or reducing sugar ..hence the term monosachharides
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    (Original post by Mushi123)
    I wrote since both of them are composed of single units and are made of carbohydrates or reducing sugar ..hence the term monosachharides
    really not sure about that. In retrospect I kinda think It wasn't as easy as I initially though. Still want to scrape an A.
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    I guess they wanted us to justify the two parts of the term .."mono" and "sachharide" hence the explanation..it was of 2 marks...should get 1 at least
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    I wrote because they consist of one sugar unit and both don't contain glycosidic bonds

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    I also wrote the single unit and more unit point, and I mentioned the sweet taste in mono but no sweet taste in poly..
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    hello could someone please give me a good description of how crossing over and independent assortment result in genetic variation?
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    (Original post by hm1234)
    hello could someone please give me a good description of how crossing over and independent assortment result in genetic variation?
    Hey

    -Both are features of meiosis
    -Meiosis is important as it reduces chromosome number in gametes from 46 to 23 , so from diploid to haploid and creates genetic variation.

    Independent/random assortment
    -Means the number of chromosomes (out of 23) that a gamete receives that are from the paternal (male) or maternal (female) side is determined by chance (randomly).
    -This leads to genetic variation in gametes because the estimated number of paternal-maternal chromosome combinations is over 8'000'000!

    Crossing over/Recombination
    -Large multi-enzyme complexes 'cut' and 'stitch' parts of paternal and maternal chromatids together.
    (Homologous pair of chromosomes next to each other 'cross over' their chromatids making an X shape called chiasma, chromatids break and recombine.The location at which the chromatids break is called chiasmata).
    -This leads to genetic variation because chromatids have exchanged genetic information and because errors in the process can lead to mutations which will introduce new combinations
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    J
    (Original post by AvWOW)
    both have a general formula of C6H12O6 and are the simplest molecules that have not undergone a condensation reaction :/ Not so sure if it's right
    same
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    Can anyone explain X chromosome inactivation, please?
    EDIT: do we even have to know about it?
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    (Original post by PinkRhinos)
    Can anyone explain X chromosome inactivation, please?
    EDIT: do we even have to know about it?
    This only occurs in females because they contain 2x-chromosome so double the genetic material in which one x chromosome in inactivate in the nuclues during embryo development and passed to embryonic cells. It is inactivated by supercoiling of chromosome forming a mass known as Barr body

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    any predictions for unit 2 guys?
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    (Original post by PinkRhinos)
    EDIT: do we even have to know about it?
    Don't think so , I don't remember seeing this in any of the past papers..
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    (Original post by DK 96)
    Don't think so , I don't remember seeing this in any of the past papers..
    From what I heard we don't need to know X chromosome inactivation and epistatis... can anyone conform this?
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    we have to have an idea, it is afterall a HSW box and so questions can be based on it.. all u have to do is read it
 
 
 
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