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

Q: Rod is the general shape of centrioles.

A: What is the general shape of centrioles?
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Q: Mercury is the name of the smallest planet in our solar system, which is also nearest to the sun.

A: What is the name of the smallest planet in our solar system, which is also nearest to the sun?
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Q: All cells undergo cell division during a lifetime, but when this process is out of control, cancer results.

A:
All cells undergo what during a lifetime, but when this process is out of control, cancer results?
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