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

Q: Most hormones are produced by the endocrine system.

A: Most hormones are produced by which human organ system?
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Q: Vesicles are basic tools of the cell for organizing metabolism, transport, and storage of molecules.

A: What are basic tools of the cell for organizing metabolism, transport, and storage of molecules?
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Q: They can exist in the form of atoms or molecules of the following is not a description of compounds.

A:
Which of the following is NOT a description of compounds?
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