Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

[EX Q]: A concave lens is thicker at the edges than it is in the middle.
[EX A]: What type of lens is thicker at the edges than it is in the middle?

[EX Q]: Thermoregulation is the process when animals maintain an internal temperature.
[EX A]: What is the process when animals maintain an internal temperature?

[EX Q]: Biochemical reactions take place inside the organisms' cells.
[EX A]:
Where do biochemical reactions take place?