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    The rate of photosynthesis in the pondweed is affected by light intensity.
    Describe a method you could use to investigate this.
    You should include:
     what you would measure
     variables you would control.

    [6 marks]
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    Have you done this practical in class?
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    (Original post by Harry.Y)
    The rate of photosynthesis in the pondweed is affected by light intensity.
    Describe a method you could use to investigate this.
    You should include:
     what you would measure
     variables you would control.

    [6 marks]
    Ill give a couple quick tips for you to branch from:
    in photosynthesis oxygen is created. (you can use leaf cuttings with the air pulled out of them and put that in CO2 rich water) then set up numerous ones of these with different light intensities to see if the questions is right.
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    Measure the distance between the pondweed beaker and the lamp. Keep size of pondweed, temperature, and volume of water used the same for each test. To work out the rate of each test, count how many Oxygen (o2) bubbles are given off.
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    (Original post by EdexcelAreIdiots)
    Have you done this practical in class?
    Yes, just want to know how to get this question for full marks
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    Name:  WhatsApp Image 2017-09-25 at 20.02.28.jpeg
Views: 18
Size:  95.3 KBAttachment 692048692050
    (Original post by Harry.Y)
    The rate of photosynthesis in the pondweed is affected by light intensity.
    Describe a method you could use to investigate this.
    You should include:
     what you would measure
     variables you would control.

    [6 marks]
    Hey, I have attaced a pic(hope it's clear) that will give a detailed answer for your question.
    You have to measure the temperature to make sure its constant, the number of bubbles formed is also counted to relate to the level of photosynthesis.
    Temperature remains constant, while the distance between the lamp and pondweed is controlled.
    Hope this helps..
    Attached Images
     
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    (Original post by Thachi3)
    Name:  WhatsApp Image 2017-09-25 at 20.02.28.jpeg
Views: 18
Size:  95.3 KBAttachment 692048692050

    Hey, I have attaced a pic(hope it's clear) that will give a detailed answer for your question.
    You have to measure the temperature to make sure its constant, the number of bubbles formed is also counted to relate to the level of photosynthesis.
    Temperature remains constant, while the distance between the lamp and pondweed is controlled.
    Hope this helps..
    Thank you very much!
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    How much will i get if I answer this to the question?

    "Place a weed in a test tube. You can keep the temperature constant by water bath and to measure using a thermometer. To keep the test fair, place the pond weed in boiling tube with same volume of water. Change the light intensity by moving the lamp so as to alter the distance between lamp and pondweed. Count the amount of bubbles for exactly one minute and no longer, to keep the test fair. Do each experiment 3 times and take an average to spot anomalies easily."
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    (Original post by President Hawk)
    Well this thread isn't gonna award me with some rep for a witty comment! I'm 'outta' here! *Sprints off frantically in search of another thread*
    So actually you used this website because you wanna get rep from someone and show off?

    TBH I think this site is for helping people, the rep is just to motivate you to help people. And gaining rep is to show how helpful you are, but not how cool you are

    Thanks a lot
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    (Original post by Harry.Y)
    How much will i get if I answer this to the question?

    "Place a weed in a test tube. You can keep the temperature constant by water bath and to measure using a thermometer. To keep the test fair, place the pond weed in boiling tube with same volume of water. Change the light intensity by moving the lamp so as to alter the distance between lamp and pondweed. Count the amount of bubbles for exactly one minute and no longer, to keep the test fair. Do each experiment 3 times and take an average to spot anomalies easily."
    I suppose that's enough for GCSE's cuz according to the mark scheme this is enough. But, I always try to write extra so I advixe you to do so, then even if one point is not right there is always another with which you can score
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    (Original post by Thachi3)
    I suppose that's enough for GCSE's cuz according to the mark scheme this is enough. But, I always try to write extra so I advixe you to do so, then even if one point is not right there is always another with which you can score
    Thanks a lot
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    (Original post by Harry.Y)
    Thanks a lot
    Welcome
 
 
 
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