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

Q: Chordates include vertebrates and invertebrates that have a notochord.

A: Chordates include vertebrates and invertebrates that have what?
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Q: Potential energy type of energy is possessed by autumn leaves before they fall.

A: What type of energy is possessed by autumn leaves before they fall?
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Q: Saliva secretion initiates chemical digestion while also protecting the oral cavity.

A:
What secretion initiates chemical digestion while also protecting the oral cavity?
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