本题目来源于试卷: Form and Function B.6 Gas Exchange，类别为 IB生物学
[单选题]
Which of the following 9cc8 ./ ywxv9 lovbqb9k+taz+ takes placzcynbg*o 4qj6rb4rm: ytfva:b16h26e during exhalation?
I. The diaphragm forms a dome shape
II. Internal intercostal muscles contract
III. Pressure increases inside the thorax
A. I only
B. II only
C. I and III only
D. I, II and III
参考答案: D
本题详细解析:
During exhalation, the diaphragm relaxes and lifts upwards to form a dome shape (Statement I). The internal intercostal muscles contract and pull the ribcage inwards and downwards (Statement II). This causes the volume inside the thorax to decrease which increases pressure inside the thorax (Statement III). Thus the air is forced out of the lungs.
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