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    Thought of a question.

    How do naked mole rats prevent against oxidative damage?
    Reactive oxygen species (ROS) are small, highly reactive, oxygen–containing molecules that are naturally generated in small amounts during the body’s metabolic reactions and can react with and damage complex cellular molecules such as fats, proteins, or DNA. The naked mole rats have the ability to reduce their metabolism during hard stress, therefore prevent ageing induced damage from oxidative stress.
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    Hey guys, quick question, The Sodium/Potassium pump, i understand that if many action potentials occur in a neurone then many Na+ ions will be within the cell and so the pump restores the concentrations back to the original level across the membrane.

    Im stuck as to what else we need to know about the pump so if someone could write a small passage describing how they work and when :P thankyou!
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    I can't start any past papers until thursday afternoon I'm basically screwed for this exam
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    (Original post by ItsDatGuy)
    I can't start any past papers until thursday afternoon I'm basically screwed for this exam
    Why until then? I'm pretty screwed as well tbh. I've been so focused on Chemistry and Unit 4.
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    (Original post by Chocip)
    Can someone explain what exactly we need to know about the Human Genome Project? The textbook kind of rambles and the specification wasn't very helpful.

    Posted from TSR Mobile
    I don't think you need to know a lot just what it is (sequence of DNA in human species) and advantages and disadvantages of it
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    Quick question: What would happen if the temperature increases during the Respirometer experiment?
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    (Original post by Chris-69)
    Quick question: What would happen if the temperature increases during the Respirometer experiment?
    I imagine the rate of respiration would increase due to a faster metabolism of the woodlice, therefore meaning they take in oxygen quicker.
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    (Original post by Selym95)
    I imagine the rate of respiration would increase due to a faster metabolism of the woodlice, therefore meaning they take in oxygen quicker.
    So then the pressure would be lower that it was before the temperature rise and hence the coloured liquid would not travel as far?

    Edit: Wouldn't an increase in respiration mean that more oxygen is released by the organism, increasing pressure?
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    (Original post by Chris-69)
    So then the pressure would be lower that it was before the temperature rise and hence the coloured liquid would not travel as far?

    Edit: Wouldn't an increase in respiration mean that more oxygen is released by the organism, increasing pressure?
    It would mean the opposite, aerobic respiration takes in oxygen and produces carbon dioxide as a bi-product.

    The liquid would move faster because more oxygen will be taken in by the woodlice, so the fluid would move towards the woodlice faster than usual.
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    (Original post by Selym95)
    It would mean the opposite, aerobic respiration takes in oxygen and produces carbon dioxide as a bi-product.

    The liquid would move faster because more oxygen will be taken in by the woodlice, so the fluid would move towards the woodlice faster than usual.
    Oh right, yes. Thanks!
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    could someone please explain how the transcription factor work? we need to know two different processes which is for peptide and steroid hormones right? thanks in advance.
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    (Original post by Chris-69)
    What would people say are the advantages and disadvantages of a simple respirometer and u-tube respirometer?
    Simple respirometer = Advantages - Very simple to set up; minimal number of connections makes a good seal easier to obtain.
    Disadvantages - Doesn't allow you to reset it; it needs a control tube used along side it. No scale, so measurements less likely to be accurate.

    U-tube respirometer = Advantages - Does not need to have an additional control as the second tube balances out the effects of changes of temperature or atmospheric pressure. The syringe allows you to move the liquid in the U to reset the apparatus.
    Disadvantages - Tendency for connections to leak. Can be expensive.

    Hope this helps Chris
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    Hi can anyone please look at question 5c(i) January 2011 paper - link below
    http://www.edexcel.com/migrationdocu...e_20110127.pdf
    and this is the markscheme
    http://www.edexcel.com/migrationdocu...s_20110309.pdf

    I do not understand this question or the answer, could anyone please explain it to me?
    Thanks!
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    (Original post by hayleyvictoria)
    Simple respirometer = Advantages - Very simple to set up; minimal number of connections makes a good seal easier to obtain.
    Disadvantages - Doesn't allow you to reset it; it needs a control tube used along side it. No scale, so measurements less likely to be accurate.

    U-tube respirometer = Advantages - Does not need to have an additional control as the second tube balances out the effects of changes of temperature or atmospheric pressure. The syringe allows you to move the liquid in the U to reset the apparatus.
    Disadvantages - Tendency for connections to leak. Can be expensive.

    Hope this helps Chris
    Thank you!
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    (Original post by EstebanK0)
    Why until then? I'm pretty screwed as well tbh. I've been so focused on Chemistry and Unit 4.
    ive got 3 exams this week :/
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    (Original post by ItsDatGuy)
    ive got 3 exams this week :/
    Same :/

    Which exams do you have?
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    What experiments do we need to be aware of? I can't remember the experiments we did :|
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    (Original post by rudizzy123)
    What experiments do we need to be aware of? I can't remember the experiments we did :|
    As in core practicals?
    -Habituation
    -Spirometer
    -Respirometer
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    Anyone compiled a list of topics that may come up for the pre release article?
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    hey, does anyone have some example questions for the naked mole rats article ? could you please upload it? any suggestions on what is likely to come up? im so stuck on it!
 
 
 
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