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O-LevelBiologyPlant Nutrition5090/11 · Oct/Nov 2019 · Q281 Mark

Four students are studying a pond ecosystem on a bright sunny day. They see the underwater plants giving off bubbles. What is the explanation of this observation?

AThe bubbles are carbon dioxide produced during photosynthesis. The plants are getting their energy from the Sun.
BThe bubbles are carbon dioxide. The plants are getting their energy for photosynthesis from respiration.
CThe bubbles are oxygen produced during photosynthesis. The plants are getting their energy from the Sun.
DThe bubbles are oxygen. The plants are getting their energy for photosynthesis from the minerals absorbed through their roots.

✓ Correct answer

C: The bubbles are oxygen produced during photosynthesis. The plants are getting their energy from the Sun.

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About this question

Topic
Plant Nutrition, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source
O-Level Biology, Oct/Nov 2019 Paper 1 Variant 1, question 28.

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