Science question help

Have you done this practical in class?

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..

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*

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

Thanks a lot