Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Reptiles are described by the term ectothermic, which means their internal temperature depends on the temperature of their environment.

Answer: Reptiles are described by what term that means their internal temperature depends on the temperature of their environment?


Question: Carbon 14 isotope of carbon is typically used to date ancient items.

Answer: What isotope of carbon is typically used to date ancient items?


Question: A jellyfish does not have a circulatory system.

Answer:
Name the type of system that a jellyfish does not have?