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    Hey, I had my OCR AS Biology ISA today on the effect of substrate concentration on enzyme activity. I think the enzyme was catalase but I can't really remember.
    We had to set up a water bath and fill a 50cm3 measuring cylinder with water turn in upside down and fit it in the clamp with minimal if any at all air bubbles.
    I’m always getting confused between what is a human error and what is an actual limitation of the experiment. I’m guessing that the air bubbles come under human error as it is possible to set the experiment up without them.
    However factors such as the conical flask not being completely dry between each repeat, the difficulty in stopping/starting the stopwatch at the correct time, some oxygen escaping between the time the reactants are added together etc.
    Can anyone clear this up for me? Thanks guys
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    (Original post by tssf_skye)
    Hey, I had my OCR AS Biology ISA today on the effect of substrate concentration on enzyme activity. I think the enzyme was catalase but I can't really remember.
    We had to set up a water bath and fill a 50cm3 measuring cylinder with water turn in upside down and fit it in the clamp with minimal if any at all air bubbles.
    I’m always getting confused between what is a human error and what is an actual limitation of the experiment. I’m guessing that the air bubbles come under human error as it is possible to set the experiment up without them.
    However factors such as the conical flask not being completely dry between each repeat, the difficulty in stopping/starting the stopwatch at the correct time, some oxygen escaping between the time the reactants are added together etc.
    Can anyone clear this up for me? Thanks guys
    In iSA you should never never never ever say human error!!
    its inaccuracy,or error or equipment only!!
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    (Original post by Future-doc)
    In iSA you should never never never ever say human error!!
    its inaccuracy,or error or equipment only!!
    Yeah, but how do I distinguish between a limitation and a human error. So that in the evaluative I don't say it's a limitation when it's a human error?
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    U just say that it makes the results less reliable
    But if u blame yourself u
    lose marks!
 
 
 
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