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: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the capillaries.

Answer: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the what?

Question: Proteins are long chains of amino acids.

Answer: What are long chains of amino acids?

Question: Gravity force increases a slide downhill and decreases a slide uphill.

Answer:
What force increases a slide downhill and decreases a slide uphill?