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    (Original post by corey7695)
    because the rubp cannot be fixed by carbon dioxide (or just very slowly), which is needed to convert it to gp, so it kinda just stays there with nowhere to go
    Can you explain the relative concentrations of RuBP TP and GP as temperature increases (ignoring effect of oxigenase activity of RuBP)
    For example from 5 degrees to 10 degrees Celsius

    The rate of all the reactions would increase
    But they wouldn't necessarily increase by the same factor
    And it can't be RuBP TP and GP all increase in concentrations because then you've introduced atoms from nowhere, haven't you?

    Any ideas?


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    Can anyone on here help me with the evaluative on invertebrates? I've got it after these easter hols...I'm on a U for these assessments, so if anyone can help me please do so! It's my last eval!
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    (Original post by Hilton184)
    Can you explain the relative concentrations of RuBP TP and GP as temperature increases (ignoring effect of oxigenase activity of RuBP)
    For example from 5 degrees to 10 degrees Celsius

    The rate of all the reactions would increase
    But they wouldn't necessarily increase by the same factor
    And it can't be RuBP TP and GP all increase in concentrations because then you've introduced atoms from nowhere, haven't you?

    Any ideas?


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    Ah. This is a guess. Completely.
    Increase in both rate of CO2 fixation and light dependent reaction, therefore more ATP and NADPH. ATP and NADPH react to convert GP to TP, and then TP to RuBP. I guess if the CO2 concentration doesn't increase as temp does it could become the limiting factor, so then there would be a build up of RuBP, and a decrease in GP and TP concentrations.
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    (Original post by AnnekaChan173)
    Ah. This is a guess. Completely.
    Increase in both rate of CO2 fixation and light dependent reaction, therefore more ATP and NADPH. ATP and NADPH react to convert GP to TP, and then TP to RuBP. I guess if the CO2 concentration doesn't increase as temp does it could become the limiting factor, so then there would be a build up of RuBP, and a decrease in GP and TP concentrations.
    That's pretty much it. Before temperature becomes a limiting factor and is simply increasing reaction rates, the rate of all enzyme controlled reactions is increased as substrates/enzymes have more kinetic energy, more frequent successful collisions (etc. etc. as at AS). Once temperature is high enough to become a limiting factor (above 25 degrees celcius), the oxygenase activity of Rubisco increases more than its carboxylase activity, so photorespiration exceeds photosynthesis. This means that ATP and reduced NADP from the light-dependent stage are wasted, and the overall rate decreases. At very high temperatures, protein structure would be disrupted, and enzymes would be denatured. High temperature also increases water loss by transpiration, so triggering a stress response in the plant (abscisic acid is released), to close the stomata and prevent wilting. This would also decrease the rate of photosynthesis, as carbon dioxide availability will be lower.
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    (Original post by [email protected])
    That's pretty much it. Before temperature becomes a limiting factor and is simply increasing reaction rates, the rate of all enzyme controlled reactions is increased as substrates/enzymes have more kinetic energy, more frequent successful collisions (etc. etc. as at AS). Once temperature is high enough to become a limiting factor (above 25 degrees celcius), the oxygenase activity of Rubisco increases more than its carboxylase activity, so photorespiration exceeds photosynthesis. This means that ATP and reduced NADP from the light-dependent stage are wasted, and the overall rate decreases. At very high temperatures, protein structure would be disrupted, and enzymes would be denatured. High temperature also increases water loss by transpiration, so triggering a stress response in the plant (abscisic acid is released), to close the stomata and prevent wilting. This would also decrease the rate of photosynthesis, as carbon dioxide availability will be lower.
    Thank-you both of you.

    So increasing temperature:
    --> increases GP concentration
    --> increases TP concentration
    --> decreases RUBP concentration

    Providing the oxygenase activity of rubisco does not come into play.




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    Is anyone else struggling with genomes and gene technologies i find some of the process confusing and the books that i have don't say the same stages any help?
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    The drosophila melanogaster - How much do we need to know? Surely not how it develops!:confused:
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    (Original post by O-M-Y)
    The drosophila melanogaster - How much do we need to know? Surely not how it develops!:confused:
    Which part of the spec is this? Homeobox gene?

    If so, then my teacher has said to familiarise ourselves with how it works with the drosophilia melanogaster example but we could potentially be asked to apply what we know about the homeobox gene to another organism. Same for the lac operon.
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    (Original post by O-M-Y)
    The drosophila melanogaster - How much do we need to know? Surely not how it develops!:confused:
    Pretty much nothing, that spread in the book is an absolute joke. We're more likely to be asked about homebox genes and another organism like the girl above me has said know what they do and how they do it.
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    Hi, could someone please explain what primary and secondary metabolites mean, it doesn't make sense to me in the book. Thanks!
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    (Original post by CamilleClarke)
    Hi, could someone please explain what primary and secondary metabolites mean, it doesn't make sense to me in the book. Thanks!
    Primary metabolites: things that an organism usually makes in metabolic processes, like amino acids
    Secondary metabolites: things an organism wouldn't usually make, or would make under certain conditions (penicillin, insulin etc)
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    (Original post by CamilleClarke)
    Hi, could someone please explain what primary and secondary metabolites mean, it doesn't make sense to me in the book. Thanks!
    Primary metabolites are basically things that are made during when cells are growing or products of respiration (the things required for division in the exponential phase - e.g. amino acids, ethanol (if it's yeast and no oxygen) and so on)

    Secondary metabolites are compounds produced when supplies are running low and competition starts happening. One example is that antibiotics are produced to kill rival bacteria so they have more food

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    Well that the first past paper i have done for the second unit in biology... They take soo long to do!! D:
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    Has everyone already finished all the modules for unit 2?
    We've sill got modules 3 and 4 to do and I'm starting to panic

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    (Original post by cforcoldplay)
    Has everyone already finished all the modules for unit 2?
    We've sill got modules 3 and 4 to do and I'm starting to panic

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    I haven't done 4, and at school we still have a few lessons of 2 left, but I've already written my notes on it
    Don't panic though, apparently module 4 is ok, and module 3 is doable
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    Unit 1 learnt.

    Past papers here I come
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    (Original post by Solarburst)
    Unit 1 learnt.

    Past papers here I come
    same here man, looks like we're working on the same wavelength haha
    what course are you doing?
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    Does anyone understand the different gene therapies? please
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    (Original post by AnnekaChan173)
    I haven't done 4, and at school we still have a few lessons of 2 left, but I've already written my notes on it
    Don't panic though, apparently module 4 is ok, and module 3 is doable
    Module 4 seems very similar to psychology I've seen things on dopamine and types of learning (operant and classical conditioning) which I'm doing right now in psych. Its module 3 I'm worrying about especially since I'm not too fond of ecosystems etc

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    (Original post by cforcoldplay)
    Module 4 seems very similar to psychology I've seen things on dopamine and types of learning (operant and classical conditioning) which I'm doing right now in psych. Its module 3 I'm worrying about especially since I'm not too fond of ecosystems etc

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    It's actually surprisingly ok! You could honestly learn it on your own tbh
 
 
 
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