A student investigated respiration in three different organisms - Edexcel - GCSE Biology - Question 9 - 2019 - Paper 1
Question 9
A student investigated respiration in three different organisms. Red hydrogen carbonate indicator was placed in each of three test tubes. Gauze was placed in each te... show full transcript
Worked Solution & Example Answer:A student investigated respiration in three different organisms - Edexcel - GCSE Biology - Question 9 - 2019 - Paper 1
Step 1
State two ways this method could be improved to make the results for these three organisms more comparable.
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Answer
Use the same volume of red hydrogen carbonate indicator in each test tube: This would ensure that the initial conditions for detecting changes in carbon dioxide concentration are uniform across all test tubes.
Ensure that the temperature is kept constant for all test tubes: Temperature can affect the rate of respiration, so maintaining the same temperature would help in obtaining more reliable and comparable results.