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Investigate and describe how light and dark conditions affect gas exchange in an aquatic plant using a hydrogencarbonate indicator solution.

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Cambridge IGCSE BiologyPlant nutritionCore contentPractical objective

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Investigate and describe how light and dark conditions affect gas exchange in an aquatic plant using a hydrogencarbonate indicator solution

This point belongs to Photosynthesis, especially Photosynthesis outcomes.
You need to be able to investigate and describe how light and dark conditions affect gas exchange in an aquatic plant using a hydrogencarbonate indicator solution.
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DescribeInvestigate

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Paper 6 structured question: Photosynthesis

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Method

1. Fill a test tube with hydrogencarbonate indicator solution. 2. Place a piece of aquatic plant (e.g., Elodea) in the test tube. 3. Place the test tube in bright light for 10 minutes and observe the color change. 4. Repeat the experiment by placing the test tube in complete darkness for 10 minutes and observe the color change. 5. Record the color changes in both conditions.

Variable	Description
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a
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