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

Q: Amount of salt are aquatic biomes often classified.

A: How are aquatic biomes often classified?
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Q: Processing of filtrate in the proximal tubule helps maintain the ph level in body fluid.

A: Processing of filtrate in the proximal tubule helps maintain what level in body fluid?
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Q: Heterotrophs is another name for consumers.

A:
Heterotrophs is another name for what group?
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