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A-LevelBiologyTransport in mammals9700/12 · Oct/Nov 2020 · Q271 Mark

Why is the mammalian circulatory system described as a double circulation?

ABlood flows twice through the heart in one complete cardiac cycle.
BBlood flows twice through the heart in one complete circuit of the body.
CBlood remains within arteries, capillaries and veins.
DBlood transports both oxygen and carbon dioxide.

✓ Correct answer

B: Blood flows twice through the heart in one complete circuit of the body.

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About this question

Topic
Transport in mammals, A-Level Biology (syllabus 9700). Multiple choice, 1 mark.
Source
A-Level Biology, Oct/Nov 2020 Paper 1 Variant 2, question 27.

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