Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
--------
Question: Ectothermic vertebrates control body temperature to just a limited extent from the outside by changing behavior.

Answer: What type of vertebrates control body temperature to just a limited extent from the outside by changing behavior?


Question: Lipids are available to the body from three sources.

Answer: Lipids are available to the body from how many sources?


Question: For an exothermic chemical reaction, energy is given off as reactants are converted to products.

Answer:
For an exothermic chemical reaction, energy is given off as reactants are converted to what?