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

Q: A skeleton that consists of hard, mineralized structures located within the soft tissue of organisms is called endoskeleton.

A: A skeleton that consists of hard, mineralized structures located within the soft tissue of organisms is called what?
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Q: Diffusion is the term for the movement of molecules from an area of high concentration to an area of low concentration.

A: What is the term for the movement of molecules from an area of high concentration to an area of low concentration?
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Q: A calorie is used to express the amount of energy in food.

A:
Which unit is used to express the amount of energy in food?
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