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    (Original post by Kidms001)
    Chemical Biology me :yep: .. Lets me do Chemistry while getting in some immunology modules :love: .. Zoology sounds amazing though

    And your brain won't let you down in such an important situation :noway: .. After watching loads of Biology programmes on Discovery, I'm very sure of it :holmes:
    Ahh nice Haha yeah, lots of evolution and ecology and less plant hormones and biotechnology

    Okay I'll trust you on that one
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    (Original post by TobeTheHero)
    could you please elaborate on this
    If my internet holds out and nobody gets there first, sure!

    How I understand it:

    • The myosin heads try to attach to form cross-bridges on the actin filament, however, it is normally covered by troponin and tropomyosin.
    • Calcium ions non-competitively inhibit the troponin so that it changes shape, moving troponin and tropomyosin away from the binding area, allowing cross-bridges to form.
    • The heads bend, moving the actin along (contraction). This is now a stable form.
    • ATP is required to bend the head back to it's orginal position, so it is hydrolysed into ADP + P.
    • Repeat if there are still Calcium ions around.


    Hope that helps
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    (Original post by atman7)
    ah sorry, click on it again in a while and it should be sorted that happens sometimes on the upload site. Sorry about that. I'm missing 3 files too in the pack which I've also attached in this post.
    Do you have these, but for everything? :P
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    (Original post by M_I)
    Whats the graduation of response?
    This is how strong the contraction is. Running and lifting requires stronger contraction than walking and reading a book (for example). Therefore the brain controls how many neuromuscular junctions (motor units) get stimulated depending on the requirement. This is graduation of response
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    (Original post by Kaph)
    I'm trying to work out the mark I roughly need to get on the paper, so I'm trying to work out my current UMS.

    How do I do the weighting/etc? Like on my results from my sixth I have the mark, I assume this is UMS? What's the UMS out of for the Jan/June papers?

    And for the ISAs? I had a quick scout on OCR, but I'm not sure where to start.

    Thanks
    It's 480/600 for an A
    420/600 B
    360/600 C

    The jan papers are out of 90 ums, the june ones are out of 150 and the coursework is out of 60.
    Yeah, the results slip from AS will have your ums marks from last year for each module so just add them up, and from Jan if you did f214 then
    A2 coursework is a bit more tricky, no one knows what the grade boundaries will be, but if you know what you got out of 40 for this year and last year, you can estimate what UMS you'll get for A2 coursework by using the ums you got from AS coursework
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    For the genetic engineering golden rice example do we need to know the name of the genes and the bacteria the plasmid is taken from?
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    (Original post by ManPowa)
    Unless your asked A question, worded so horrible and vague that you end up leaving it out. Even though its simple biology, if i say. Errrr OCR :eek:
    i guess, yeah. I'm hoping for the whole "how does meiosis lead to variation within a population" kind of question.
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    (Original post by Kidms001)
    If my internet holds out and nobody gets there first, sure!

    How I understand it:

    • The myosin heads try to attach to form cross-bridges on the actin filament, however, it is normally covered by troponin and tropomyosin.
    • Calcium ions non-competitively inhibit the troponin so that it changes shape, moving troponin and tropomyosin away from the binding area, allowing cross-bridges to form.
    • The heads bend, moving the actin along (contraction). This is now a stable form.
    • ATP is required to bend the head back to it's orginal position, so it is hydrolysed into ADP + P.
    • Repeat if there are still Calcium ions around.


    Hope that helps
    ATP is used as energy to break the myosin head off from the Actin, I thought?
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    is there a jan 2010 f215 paper?
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    (Original post by DrDr)
    ATP is used as energy to break the myosin head off from the Actin, I thought?
    :yep: .. That's what I meant by moving it back to it's original position. Sorry if I didn't make that clear enough
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    (Original post by DrDr)
    ATP is used as energy to break the myosin head off from the Actin, I thought?
    When ATP binds to the head, it breaks the cross bridges between the myosin head an actin.
    When it's hydrolysed the head bends backwards
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    Explain why plants need to respond to their environment in terms of the need to avoid predation and Abiotic stress
    I understand why the tropisms would help against abiotic stress....but I don't understand how plants avoid predation?
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    (Original post by kej817)
    Explain why plants need to respond to their environment in terms of the need to avoid predation and Abiotic stress
    I understand why the tropisms would help against abiotic stress....but I don't understand how plants avoid predation?
    avoid bein eaten, so grazing
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    (Original post by kej817)
    Explain why plants need to respond to their environment in terms of the need to avoid predation and Abiotic stress
    I understand why the tropisms would help against abiotic stress....but I don't understand how plants avoid predation?
    I presume via methods of Geotropisms, plants can 'climb' away from predation, its the only way i can think of?
    Other than defence mechanisms such as a cactus or fly trap has.. however i think that is a much more complicated example than we need to know about!
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    (Original post by Kidms001)
    This is how strong the contraction is. Running and lifting requires stronger contraction than walking and reading a book (for example). Therefore the brain controls how many neuromuscular junctions (motor units) get stimulated depending on the requirement. This is graduation of response
    Thanks.
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    (Original post by CoventryCity)
    For the genetic engineering golden rice example do we need to know the name of the genes and the bacteria the plasmid is taken from?
    Also can somebody link to me some good resources or give me a brief summary of what we need to know for DNA probes and sequencing the genome. I understand about PCR and electrophoresis but don't understand the chain termination method or sequencing the genome using BACs
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    (Original post by raj16)
    is there a jan 2010 f215 paper?
    Nope, the first one was june 2010
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    (Original post by raj16)
    avoid bein eaten, so grazing
    But how does a tropism actually prevent the plant being eaten..?
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    (Original post by Kidms001)
    :yep: .. That's what I meant by moving it back to it's original position. Sorry if I didn't make that clear enough
    Yeah I kinda always imagined the Myosin head acting like an elastic band, and that the ATP did all the work breaking it off, then it just "pings" back into place. My brain works in horrendously unscientific ways...

    Just realised ATP does both, lol :s
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    (Original post by raj16)
    is there a jan 2010 f215 paper?
    no
 
 
 
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