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: The cytoskeleton holds cell organelles in place within the cytoplasm.

Answer: What part of the cell holds cell organelles in place within the cytoplasm?


Question: 600 million many years ago may the earliest fungi have evolved.

Answer: How many years ago may the earliest fungi have evolved?


Question: Anaerobic respiration occurs if oxygen cannot be obtained at a sufficient rate.

Answer:
What occurs if oxygen cannot be obtained at a sufficient rate?