Which statement about reptiles is true?

Which statement about reptiles is true?

• A. They are ectothermic and require a heat source
• B. They are endothermic and do not require external heat
• C. They can survive without water
• D. They only need ultraviolet light

Answer: (A)

Reptiles regulate their body temperature mainly through the environment, not by generating heat internally. This ectothermy means they must have access to external heat sources, such as basking spots, warm surfaces, or sun exposure, to reach the temperatures needed for activity, digestion, and metabolism. The idea that they are endothermic and do not require external heat would imply internal heat production like mammals and birds, which reptiles do not do. The notion that they can survive without water overlooks a basic need for hydration and moisture to support bodily functions and shedding, even though some species tolerate dry conditions for periods. The statement that they only need ultraviolet light is also inaccurate; UV can aid vitamin D synthesis in some reptiles, but a heat source and water are essential for proper physiology and husbandry.

Reptiles regulate their body temperature mainly through the environment, not by generating heat internally. This ectothermy means they must have access to external heat sources, such as basking spots, warm surfaces, or sun exposure, to reach the temperatures needed for activity, digestion, and metabolism. The idea that they are endothermic and do not require external heat would imply internal heat production like mammals and birds, which reptiles do not do. The notion that they can survive without water overlooks a basic need for hydration and moisture to support bodily functions and shedding, even though some species tolerate dry conditions for periods. The statement that they only need ultraviolet light is also inaccurate; UV can aid vitamin D synthesis in some reptiles, but a heat source and water are essential for proper physiology and husbandry.