BIO120H1 Study Guide - Exponential Growth, River Ecosystem, Permafrost
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BIO120H1 Full Course Notes
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Chapter 3 summary: although co2 is scarce in the atmosphere, it is more abundant in aquatic systems, where it dissolves to form bicarbonate ions. The availability of carbon in aquatic systems is limited, however, by the rate of diffusion of. The generality of this temperature effect has been captured in the metabolic theory of ecology: higher temperatures generally accelerate physiological processes, but can also cause proteins and other biological molecules to unfold and lose their structure and function. Together with metabolically produced heat, these factors make up the heat budget of the organism: maintenance of constant internal conditions, called homeostasis, depends on negative feedback mechanisms. Organisms sense changes in their internal environment and respond in such a manner as to return those conditions to a set point: homeostasis requires energy when a gradient between internal and external conditions must be maintained. For example, endotherms must generate heat metabolically to balance loss of heat to their cooler surroundings.
