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    (Original post by Maham88)
    is the electron transport chain part of chemiosmosis ?
    Sort of. The ETC itself isn't chemiosmosis, but the product of ETC (the proton gradient) is.

    (Original post by Shanahey)
    Can someone please explain to me local currents/circuits?? (neurones)
    Thank you
    Local currents are when Na ions diffuse slightly sideways in action potentials. When they diffuse in the direction without a refractory period (the resting section), there is a new threshold gradient. This small distance is a local current.
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    (Original post by TheLegalDealer)
    What on earth is that on about ???
    Thats F212 which was last week
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    (Original post by Beni24)
    Thats F212 which was last week
    Was that in a f324" paper ?? And what AS topics could they ask us ?
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    (Original post by Maham88)
    why is the theoretical max yield of ATP per molecule of glucose hardly reached in aerobic respiration ?
    ATP is required to actively transport pyruvate into the mitochondria
    ATP is needed to shuttle H atoms on NADH to oxidative phosphorylation
    ATP may leak through the membranes so reduces the number of H+ ions used during chemiosmosis so less ATP is generated
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    (Original post by Maham88)
    why is the theoretical max yield of ATP per molecule of glucose hardly reached in aerobic respiration ?
    ATP used to actively transport pyruvate from cytoplasm into mitochondria and Reduced NAD from gylcolysis to innermitochondial membrne

    + some protons leak through inner mitochondrial membrane so protomotive force reduced to make ATP
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    Hey everyone.

    Respiratory substrates question - if the RQ is 0.75, is this lipid of proteins? Saw it on a past paper along with 0.95) and just didn't understand the mark scheme!

    Thanks,

    Good luck everyone!
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    if you write fructose (1,6) diphosphate instead of fructose (1,6) bisphosphate would that be right ?
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    (Original post by daisystones)
    Hey everyone. <br />
    <br />
    Respiratory substrates question - if the RQ is 0.75, is this lipid of proteins? Saw it on a past paper along with 0.95) and just didn't understand the mark scheme!<br />
    <br />
    Thanks
    <br />
    Good luck everyone!
    It will be a combination of the 3 but predominantly lipids due to depleted glucose availability.

    You probably always get a mark for saying that proteins are an unlikely substrate
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    (Original post by TheLegalDealer)
    Was that in a f324&quot; paper ?? And what AS topics could they ask us ?
    Literally anything. I came across a unit 5 paper that talked about transpiration stream
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    (Original post by loperdoper)
    I would say it's worth being aware of the basics of the method (just in case they throw in an application of knowledge question), although learning it until you can design it perfectly or anything is just a waste of time.
    Thanks, much appreciated dude.
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    (Original post by HeyThereHarry)
    Outline the use of biochemical tests to determine the presence of biological molecules in a solution. (5)
    Hi, what past paper is this from? Seems quite a vague question so just want to see the context its been put in? Thanks
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    Could someone please explain what we need to know about respiratory substrates and RQs? (:
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    Useful link with mistakes in the OCR heinamann textbook (with the brain on front), just so then no one learns anything wrong! Worst thing is finding out you've made a mistake, with no fault of yours!

    https://www.whatdotheyknow.com/reque...nd_futyre_exam

    Hope you find it helpful!
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    (Original post by goonieskellie)
    Could someone please explain what we need to know about respiratory substrates and RQs? (:
    The spec says
    "Define the term respiratory substrate.
    Explain the difference in relative energy values of carbohydrate, lipid and protein respiratory substrates."

    The first one is pretty self explanatory. The second you want to know that lipids have the most, as they have more hydrogen (reduce more NAD per molecule). Carbohydrates are used first as they can enter glycolysis straight away, whereas protein/lipids have to be broken down into glycerol/glucose first.
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    Do we need to know about peritoneal dialysis in detail ?


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    im scared
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    (Original post by AsianBeauty)
    Do we need to know about peritoneal dialysis in detail ?


    Posted from TSR Mobile
    The spec only refers to renal dialysis, and peritoneal dialysis doesn't even appear in the cgp student book, so I wouldn't worry about it.
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    Can someone tell me how to get A*?


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    Sorry if this has been asked before, haven't read the other pages, what sort of topics are likely to come up?
    What didn't come up in last year's paper
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    (Original post by loperdoper)
    The spec only refers to renal dialysis, and peritoneal dialysis doesn't even appear in the cgp student book, so I wouldn't worry about it.
    Thank you


    Posted from TSR Mobile
 
 
 
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