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

Q: Bile acids, needed to emulsify lipids, are stored in the body in the gallbladder.

A: Where are bile acids, needed to emulsify lipids, stored in the body?
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Q: You call a substance that is not an acid or a base neutral.

A: What do you call a substance that is not an acid or a base?
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Q: Arginine amino acid do organisms incorporate into their proteins.

A:
Which amino acid do organisms incorporate into their proteins?
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