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

Q: One gram of sugar or starch provides 4 calories of energy.

A: How many calories of energy does one gram of sugar or starch provide?
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Q: Muscle groups are controlled by the motor cortex .

A: Muscle groups are controlled by what mechanism?
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Q: Methyl groups are found within amino acids.

A:
Methyl groups are found within what?
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