单词	ectotherm
释义	ectotherm /ˈɛktəʊθəːm / noun Zoology An animal that is dependent on external sources of body heat. Often contrasted with endotherm. Compare with poikilotherm.The papers cover a substantial range of physiological systems and numerous types of organisms, including ectotherms and endotherms, vertebrates, insects, plants, and bacteria.... Thus, perhaps the commonly asked question whether dinosaurs were ectotherms or endotherms is inappropriate, and it is more constructive to ask which dinosaurs were likely to have been endothermic and which ones ectothermic. Ecological studies suggest that today's endotherms (mammals and birds) generally outcompete ectotherms in their area. Derivatives ectothermic adjective ... The temperature at which the eggs of ectothermic vertebrates incubate can influence several phenotypic traits of offspring. Many ectothermic species demonstrate behavioral thermoregulation following feeding in an attempt to increase body temperature, thus increasing temperature-dependent rate processes associated with catabolism. A lack of metabolic data has made this association more difficult to assess in most ectothermic vertebrates, and little is known of any possible relationship between genome size and metabolic rate in fishes and reptiles. ectothermy noun ... Endothermy did evolve from ectothermy, and birds did evolve from dinosaurs, which we know came from ectothermic ancestors sometime in the distant past. But the apparent dichotomy between endothermy and ectothermy is misleading; rather, there is a broad spectrum of metabolic types, many of which are directly correlated with the anatomical form and function of the breathing apparatus. Dinosaur bones show no evidence of ectothermy; Mesozoic dinosaurs deposited tissues that in living tetrapods grow at rates that suggest basal metabolic rates significantly higher than those of any living non-avian reptiles.
随便看	phthalic anhydride phthalide phthalimide phthalo phthalocyanine phthalocyanine blue phthalocyanine green phthalyl phthalylsulfathiazole phthalylsulphathiazole phthanite phthiocol phthioic acid Phthiraptera phthirapteran phthiriasis phthirophagous phthisiatry phthisic phthisical phthisiogenesis phthisiogenetic phthisiologist phthisiology phthisiophobia

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