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    (Original post by eleanor97)
    Could someone explain restriction mapping please?
    RestrictionmappingRestriction mapping involves cutting DNA at variousdifferent recognition sitesFragments are then separated and identified with gelelectrophoresisWhen a plasmid is cut by R.E only one strand of DNA isproduced. Because of this combinations of R.E are used to cut the plasmid intotwo fragments. The size of the fragments produced depends on whichrestriction endonuclease are used Automation of DNAsequencing and restriction mappingMost DNA sequencing is carried out by machinesFluorescently labelled dyes are used by computerised systemsrather than radioactively labelled onesEach modified nucleotide has a colour associated with it sothat the whole process can be carried out in one test tubePCR cycles are used to speed up the processThe electrophoresis is carried out in a single narrowcapillary gel and the results are scanned by lasers and interpreted by computersoftware
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    (Original post by kiwi8397)
    if that syringe has drugs, aqa might ask you how they'll affect transmission across your synapses
    dam you aqa dam you to hell
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    Anyone just cba with this exam?
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    (Original post by Bethany_)
    What does R mean?
    It means restriction endonuclease
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    Should I look at breathing in insects/fish and also transport mediums from last year or would they be unlikely to come up?
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    Can somebody sum up Action Potentials?
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    (Original post by sofja26)
    Hi I believe that Histamines- (within the white blood cells) they react to particular allergens e.g. pollen. This will increase permeability to capillaries e.g. swelling.

    Prostaglandins (Cell membranes) Also dilate arteries causing swelling but these affect the pain receptors more due to injury by affecting blood pressure and transmission through neurones.

    The key thing to remember here is that these are chemical mediators and these are different to hormones because they affect specific/ more direct to particular cells where hormones are more direct.
    thanks
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    (Original post by bishopdon123)
    Anyone just cba with this exam?
    yup
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    (Original post by eleanor97)
    Could someone explain restriction mapping please?
    Would be appreciated.
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    (Original post by bishopdon123)
    Anyone just cba with this exam?
    Fallen asleep twice in my chair in the space of 4 hours so yep
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    Someone said on another thread that the R paper does not have a Q9 (15marks) as they do not have time to make a full paper
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    (Original post by Bustamove)
    thanks
    histamine causes itching and redness also
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    would carbon dioxide and acidity be appropriate for an ions essay? also is kidney function in the spec or is it extra?
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    (Original post by Bustamove)
    thanks
    Sorry* When I said hormones are more direct I meant that they are more widespread
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    If anyone is the slightest bit confused about PCR I found this website that has a great animation explaining it...

    http://learn.genetics.utah.edu/content/labs/pcr/
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    (Original post by tofaeal)
    Someone said on another thread that the R paper does not have a Q9 (15marks) as they do not have time to make a full paper
    Hmmm.... how vaild is this?

    they could just use and older topic from a past paper like they did in Biol 4 (used some questions from June 2010 paper)
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    (Original post by bishopdon123)
    Anyone just cba with this exam?
    The fact that they pull out bs from their hidden spec to question us on how to play with graphs is the factor which makes me agree with you.

    Its pathetic and I would advise anyone not to take bio.
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    Please help! I haven't had chance to do any past papers, are there any key points or recurring answers in the mark schemes to remember?
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    (Original post by tofaeal)
    It means restriction endonuclease
    It might as well be because this exam is gonna cut me up
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    (Original post by mujtaba.khokhar)
    Hmmm.... how vaild is this?

    they could just use and older topic from a past paper like they did in Biol 4 (used some questions from June 2010 paper)
    Maybe quite valid as R papers for other subjects in the past have had less essays on them than normal(if it is an essay subject) or less questions
 
 
 
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