Which statement accurately describes an ectotherm?

An ectotherm is an organism that relies primarily on external environmental conditions to regulate its body temperature. This means that ectotherms absorb heat from their surroundings to maintain their body warmth rather than generating their own heat through metabolic processes. For example, reptiles, amphibians, and many fish exhibit ectothermic behavior, often basking in the sun to raise their body temperature or seeking shade to cool down.

In contrast, endotherms, like mammals and birds, generate their own body heat primarily through metabolic processes, allowing them to maintain a relatively constant internal body temperature independent of the environment. Therefore, the defining characteristic of ectotherms is their dependence on the external environment for temperature regulation, making the accurate statement that they absorb heat from their environment.