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Photosynthesis

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Question 3

A student investigated how light intensity and temperature affect the rate of photosynthesis in a suspension of the unicellular green alga Chlorella vulgaris. The rate of photosynthesis was determined by measuring the increase in dissolved oxygen concentration using an oxygen probe over a 10-minute period.

The student's results are shown in the table below:

Light intensity (arbitrary units)Temperature (∘C^\circ\text{C}∘C)Increase in dissolved oxygen concentration (mg L−1\text{mg L}^{-1}mg L−1)
2010.00.8
8010.02.4
15010.03.6
30010.03.9
2025.01.8
8025.05.4
15025.01.2
30025.09.2
2045.00.1
8045.00.2
15045.00.2
30045.00.3
a.

Identify the anomalous result in the table and describe how the student could confirm whether this result is indeed an anomaly.

[2]
b.

Suggest why the rate of photosynthesis is extremely low at all light intensities when the temperature is 45.0∘C45.0^\circ\text{C}45.0∘C.

[2]

Photosynthesis Questions

  1. A Level
  2. /Biology
  3. /Photosynthesis