Which is the equation for photosynthesis? Tick (✓) one box - AQA - GCSE Biology Combined Science - Question 1 - 2021 - Paper 1
Question 1
Which is the equation for photosynthesis? Tick (✓) one box.
C₆H₁₂O₆ + O₂ → 6CO₂ + 6H₂O
6CO₂ + 6H₂O → C₆H₁₂O₆ + O₂
6H₂O + 6CO₂ → C₆H₁₂O₆ + O₂
6CO₂ + 6H₂O → 6O₂ + ... show full transcript
Worked Solution & Example Answer:Which is the equation for photosynthesis? Tick (✓) one box - AQA - GCSE Biology Combined Science - Question 1 - 2021 - Paper 1
Step 1
Which is the equation for photosynthesis? Tick (✓) one box.
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Answer
The correct equation for photosynthesis is:
6CO2+6H2O→C6H12O6+6O2
Step 2
What was the independent variable in this investigation? Tick (✓) one box.
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Answer
The independent variable in this investigation was the distance of the pondweed from the lamp.
Step 3
Explain how an increase in temperature would affect this investigation.
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Answer
An increase in temperature would generally increase the rate of photosynthesis, as enzymes involved in the process would work faster. However, excessively high temperatures could lead to enzyme denaturation, thus reducing the rate.
Step 4
Suggest one way the investigation could be improved so the temperature of the water does not increase.
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Answer
One way to improve the investigation is to use a heat shield between the lamp and the pondweed to minimize direct heat exposure.
Step 5
Give two improvements to the investigation so the results would be more valid.
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Answer
Control the concentration of carbon dioxide in the water to ensure consistency.
Use a timer to ensure that the number of bubbles is counted over the same time period for each repetition.
Step 6
Calculate the rate of photosynthesis when the pondweed was 40 cm from the lamp.
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Answer
To calculate the rate of photosynthesis:
The number of bubbles produced in 5 minutes at 40 cm is 16.
Rate = 5 minutes16 bubbles=3.2 bubbles of gas produced per minute.
Step 7
Give one conclusion that can be made from Table 1.
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Answer
As the distance from the lamp increases, the number of bubbles of gas produced decreases, indicating a negative correlation between light intensity and the rate of photosynthesis.
Step 8
Plot the data from Table 1 on Figure 2. Draw a line of best fit.
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Answer
Ensure that all points from Table 1 are plotted correctly on the graph and draw a line of best fit that accurately represents the trend of the data.
Step 9
Predict the number of bubbles that would be produced in 5 minutes if the pondweed was 60 cm from the lamp.
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Answer
Based on the trend observed in the graph, the number of bubbles produced at a distance of 60 cm can be estimated to be around 8 bubbles in 5 minutes.
