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    (Original post by Hilton184)
    June 10 F214 Q5aiii - when is the membrane most permeable to potassium ions.

    Apparently the answer is D. But the potassium ion channels open at C, so this is when the concentration gradient will be greatest, so surely this is when the membrane is most permeable to potassium ions no? I don't understand how it could possibly be half way into re-polarisation, when clearly by this point there is a much lower electrochemical gradient.
    I made the same mistake , I think C is meant to be showing closing of the sodium channel ....
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    (Original post by TheLegalDealer)
    I made the same mistake , I think C is meant to be showing closing of the sodium channel ....
    I think it's because C is meant to show when sodium ion channels are full open, the cell becomes positively charged, then D is when potassium ion channels open due to the change in potential difference and the cell becomes re polarised
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    (Original post by maisie__x)
    I think it's because C is meant to show when sodium ion channels are full open, the cell becomes positively charged, then D is when potassium ion channels open due to the change in potential difference and the cell becomes re polarised
    Yup , that makes sense cheers !
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    Hmm yeah I can see what you mean. Pretty poor diagram really if that's what they are trying to imply, because the sodium ion channels close and potassium ion channels open when +40mV is reached, not sodium ion channels close at +40mV and then half way back to resting potential potassium ion channels suddenly open.


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    does anyone know what to get for full UMS on f214?
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    (Original post by Ahsen2015)
    does anyone know what to get for full UMS on f214?
    I posted this up some time ago on the chemistry thread I think

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    Thanks, how is everyone revising for Biology?


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    Cos I'm really worried, I've had awful biology teachers this year and haven't gone through the last 2 modules of f215, so what's the best way to go over it etc


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    Can someone pls help me with this question?? Name:  Screenshot from 2015-05-29 04:20:34.png
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    (It's june 2010 2bii)
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    Use A2 biology 101 notes there quick and simple, also Mr BioTom on YouTube has some great explanation videos, and deffo look through past papers so you get the hang of things!

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    (Original post by PinkElephant16)
    Can someone pls help me with this question?? Name:  Screenshot from 2015-05-29 04:20:34.png
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    (It's june 2010 2bii)
    First just do the cross to make it clear, as you can see the phenotypic ratio is 1:1 for red eyed and white eyed if the red eyed parent is heterozygous, so that cannot be a good explanation. as we know the probability of male:female is also 1:1 so a male with red eyes should be equally as likely to get white eyes


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    (Original post by PinkElephant16)
    Can someone pls help me with this question?? Name:  Screenshot from 2015-05-29 04:20:34.png
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    (It's june 2010 2bii)
    Hopefully this makes sense

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    (Original post by huniibehi)
    Use A2 biology 101 notes there quick and simple, also Mr BioTom on YouTube has some great explanation videos, and deffo look through past papers so you get the hang of things!

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    Past papers are literally the key to success with these exams!
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    (Original post by Ahsen2015)
    does anyone know what to get for full UMS on f214?
    I made excel spreadsheets for F214 and F215 grade boundaries (including raw marks needed for full UMS). Here they are:
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    That's really helpful! Good job :top:
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    (Original post by Ahsen2015)
    Cos I'm really worried, I've had awful biology teachers this year and haven't gone through the last 2 modules of f215, so what's the best way to go over it etc


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    First time posting so I'm not sure how much help I will be. I would recommend going through some key areas in the spec.

    For Animal responses I would:
    - Know why animals need to respond to their environment (same as why plants to)
    - Ensure you know the difference in the Central Nervous system and the peripheral
    - Know what/where the Cerebrum, cerebellum, oblongata and hypothalamus do/are in the brain
    - Give a detailed account of how muscle contraction is produced (make a flowchart of the steps and keep going over it)
    - Know how a neuromuscular junction is different to a synapse (neurotransmitters/structure)
    - Differences in structure/function between voluntary, involuntary and cardiac (a lot of questions go for comparative tables so make a meaty one with as many as you can)
    - Explain how hormones and nerves are involved in flight/fight (often in longer QWC questions)

    For Animal behaviour:
    - List advantages of innate behaviour (+ some characteristics and examples)
    - Know what escape reflexes, taxes and kineses do (+ one example for each)
    - Define learned behaviour
    - Know what habituation, imprinting, classical and operant conditioning, latent and insight learning are (+ again use examples)
    - Examples and definition of social behaviour in primates (NEVER use humans as examples though as mark schemes are haters on it)
    - Know about dopamine receptor DRD4 and abnormal behaviour

    For animal behaviour you might have picked up the vibe that you need examples. Most mark schemes tend to give another mark if you give an example with a definition.

    My teacher for this had a mare so we ended up teaching ourselves. Hope this helps you out, not a clue if its what you were after
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    Can someone explain to me how to produce Golden Rice + do we have to learb the exact species involved ?
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    (Original post by TheLegalDealer)
    we have to know that ?! I just use Viruses on Qs about gene therapy
    How can you tell what vector to use ? I remember a question and the possible options were: liposomes. bacs, viruses etc etc ;/
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    Hi guys, anyone got any revision notes/resources for the synoptic element of F214 and F215?
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    Could someone kindly describe the stucture of the sliding filament model and explain how the sliding filament model works. The diagrams in the textbook look complicated.
 
 
 
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