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: Cells are small biological structures that make up all living things, including the human body.

Answer: What small biological structures make up all living things, including the human body?

Question: Gastro-esophageal sphincter sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach.

Answer: Which sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach?

Question: The difference in electric potential energy which allows for an electric charge to move from one position to another is measured by the volt si unit.

Answer:
The difference in electric potential energy which allows for an electric charge to move from one position to another is measured by what si unit?