What is the relationship between temperature and metabolic rate in organisms?

The relationship between temperature and metabolic rate in organisms is often characterized by the principle that, for many ectothermic (cold-blooded) organisms, metabolic rate generally increases as temperature rises and decreases as temperatures fall. This is largely due to the effect of temperature on enzymatic reactions and biological processes, which tend to operate more efficiently at higher temperatures up to a certain threshold.

When temperature decreases, the kinetic energy of molecules also decreases, which slows down the enzymatic reactions that drive metabolism. Consequently, as the temperature drops, metabolic processes become less efficient, leading to a decrease in metabolic rate. This phenomenon can be observed in various organisms, especially ectotherms, whose body temperatures and metabolic rates fluctuate with the environmental temperature.

In contrast, endothermic (warm-blooded) organisms have mechanisms to maintain a stable internal temperature regardless of external conditions, but even for them, extreme cold can lead to a reduction in metabolic rate as their bodily functions may slow down or require more energy to maintain temperature. However, the primary understanding in the context of this question revolves around ectothermic organisms and how their metabolic rates are influenced by surrounding temperature changes.

Thus, the correct answer reflects the biological principle that metabolic rates decrease as temperatures drop, highlighting the direct