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: Natural resource type of resource is limited in supply and cannot be replaced except over millions of years.

Answer: What type of resource is limited in supply and cannot be replaced except over millions of years?

Question: Vesicles are basic tools of the cell for organizing metabolism, transport, and storage of molecules.

Answer: What are basic tools of the cell for organizing metabolism, transport, and storage of molecules?

Question: Covalents bonds result from the overlap of atomic orbitals.

Answer:
What bonds result from the overlap of atomic orbitals?