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: All cells have the small size in common.

Answer: What do all cells have in common?


Question: In prokaryotes, a(n) genome is composed of a single, double-stranded dna molecule in the form of a loop or circle.

Answer: In prokaryotes, what is composed of a single, double-stranded dna molecule in the form of a loop or circle?


Question: Jaws and pharynx muscles are used to pump water over the gills.

Answer:
What muscles are used to pump water over the gills?