本题目来源于试卷: Interaction & Interdependence C.1 Enzymes & Metabolism，类别为 IB生物学
[单选题]
What is a characteristip s:, qf4x6:l7xe;zo0dyyae ec ttjg-r2.j8jmeh(+g* chby roe x o66g 9hat separates mammals or endotherms from ectotherms that have fluctuating bodyje*h6 try.mcg 6j2+ x(ebghj89g-o or temperatures?
A. They are able to absorb heat from external sources to maintain their body temperatures.
B. They use the heat generated from metabolic processes in their bodies to maintain their body temperature above a set lower limit.
C. They have a very efficient metabolism that does not release much waste as heat energy.
D. They can survive without eating for longer periods because they do not depend on metabolising what they eat.
参考答案: B
本题详细解析:
Endotherms tend to hc+k;bddt( :jjave a more consistent and higher baseline metabolic rate than ectotherms. Metabod j(djct b+;:klic reactions are not very efficient and so energy is dissipated as heat, therefore, Choice C is incorrect. Endotherms use the heat released to maintain their body temperature above a lower set limit, therefore Choice B is correct.
Both ectotherms and endotherms absorb heat from external sources. However, ectotherms rely on this heat to maintain their body temperature as they cannot maintain their own body temperature (Choice A).
It’s the ectotherms that can survive for long periods without eating (Choice D) as they are not dependent on metabolising what they eat to generate heat. They also tolerate variations in internal temperatures better than endotherms.
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