instruction:
Turn the given fact into a question by a simple rearrangement of words. This typically involves replacing some part of the given fact with a WH word. For example, replacing the subject of the provided fact with the word "what" can form a valid question. Don't be creative! You just need to rearrange the words to turn the fact into a question - easy! Don't just randomly remove a word from the given fact to form a question. Remember that your question must evaluate scientific understanding. Pick a word or a phrase in the given fact to be the correct answer, then make the rest of the question. You can also form a question without any WH words. For example, "A radio converts electricity into?"
question:
Fact: The leg straightens when muscle fibers get shorter.
answer:
What happens to your leg when muscle fibers shorten?


question:
Fact: Support structures of a plant are sometimes used to store water.
answer:
Where is water sometimes stored in a tree or plant?


question:
Fact: Organisms rely on a relatively narrow range of acidity.
answer:

Organisms rely on a relatively narrow range of what?