本题目来源于试卷: Interaction & Interdependence C.2 Cell Respiration，类别为 IB生物学
[单选题]
The graph below shows the chan n bd:te5cvie0f9m0 8z ges in the levels of lactate on th u + k6 xfodsrt:e8,t.de skin of athletes duri e 6uk+dox.rst:ft d,8 ng pre-training (rest), training, and recovery.
Based on the graph, which is true?
A. There was no lactate during pre-training because there was no cellular respiration.
B. As exercise intensity increased, anaerobic respiration increased.
C. During periods of exercise, lactate levels remained constant.
D. During the recovery periods, aerobic and anaerobic respiration continuously increased.
参考答案: B
本题详细解析:
Choice A – A is wrong because there was approximaa z+*yd3r0v tr8rxlr ub 8m3zmg-4oov.pm2 )itely $0.39 mmol L^{-1}$ during rest.
Choice B - During the training period, there was an increase in the intensity of exercise which required an increase in ATP synthesis. Since the ATP output of aerobic respiration was inadequate, the body also used anaerobic respiration to produce ATP. The increased rate of anaerobic respiration was evidenced by the increasing levels of lactate on the skin.
Choice C – During the training period, lactate levels increased because the intensity of exercise increased.
Choice D – During the recovery period, lactate levels decreased because the body was transitioning back to utilising aerobic respiration only.
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