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A-LevelBiologyGas exchange9700/12 · Feb/Mar 2025 · Q301 Mark

Which statements about the transport of carbon dioxide in the blood are correct? 1 Carbonic anhydrase catalyses the reaction of carbon dioxide and water to form carbonic acid. 2 Carbonic acid dissociates into hydrogen ions and hydrogencarbonate ions. 3 Some carbon dioxide combines with haemoglobin to form carbaminohaemoglobin. 4 Haemoglobin readily combines with hydrogencarbonate ions to form haemoglobinic acid.

A1, 2 and 3
B1, 2 and 4
C1, 3 and 4
D2, 3 and 4

✓ Correct answer

A: 1, 2 and 3

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About this question

Topic
Gas exchange, A-Level Biology (syllabus 9700). Multiple choice, 1 mark.
Source
A-Level Biology, Feb/Mar 2025 Paper 1 Variant 2, question 30.

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