Question
A student investigates how light intensity affects the rate of photosynthesis in pondweed. She places the pondweed at different distances from a lamp and counts the number of bubbles (oxygen) produced per minute.
(a) Identify the independent variable. (1 mark) (b) Identify the dependent variable. (1 mark) (c) Give TWO variables that should be controlled to make this a fair test. (2 marks) (d) Explain why the student should take 3 repeats at each distance. (2 marks)
6 marks · take your time before peeking.
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Generated by TopMyGrade AI · cross-check official sources before relying on the mark-scheme phrasing.