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

Q: A desmosome is a cell structure that anchors the ends of cardiac muscle fibers together.

A: A desmosome is a cell structure that anchors the ends of what fibers together?
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Q: The mesopause is at the top of the mesosphere.

A: What is at the top of the mesosphere?
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Q: Reflexes normal bodily occurrence can cause skeletal muscles to involuntarily contract.

A:
What normal bodily occurrence can cause skeletal muscles to involuntarily contract?
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