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

Q: The bones of the newborn skull are not fully ossified and are separated by large areas called fontanelles.

A: The bones of the newborn skull are not fully ossified and are separated by large areas called what?
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Q: The cytoskeleton holds cell organelles in place within the cytoplasm.

A: What part of the cell holds cell organelles in place within the cytoplasm?
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Q: Dense collagen secures together immovable joints and prevents them from moving.

A:
What secures together immovable joints and prevents them from moving?
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