Final answer:
The student's question concerns the difference between ectotherms and endotherms, with the former depending on external heat to regulate body temperature and the latter using metabolic heat to maintain a stable internal temperature.
Step-by-step explanation:
The question is asking to define the differences between ectotherms and endotherms, which are types of organisms characterized by their methods of thermoregulation. Ectotherms depend on external heat sources to warm their bodies, which means their body temperature can vary with the environment. They rely on behaviors such as basking in the sun or seeking shade to regulate their temperature. Examples include reptiles and amphibians.
Contrarily, endotherms generate warmth from their own metabolism, allowing them to maintain their body temperature within a narrow range, unaffected by external temperatures. This can involve physiological adaptations such as shivering to produce heat or sweating to cool down, and is seen in mammals and birds. Maintaining a stable body temperature ensures that their cells can function efficiently, but it requires a higher energy intake.