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O-LevelBiologyRespiration5090/12 · Oct/Nov 2018 · Q191 Mark

Why is it important that the lungs remove carbon dioxide from the body?

ACarbon dioxide is a greenhouse gas.
BCarbon dioxide is a metabolic waste product and is poisonous.
CCarbon dioxide would increase the pH of the blood.
DCarbon dioxide is needed by plants for photosynthesis.

✓ Correct answer

B: Carbon dioxide is a metabolic waste product and is poisonous.

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About this question

Topic
Respiration, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source
O-Level Biology, Oct/Nov 2018 Paper 1 Variant 2, question 19.

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