Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: Examples of organ systems in a human include the skeletal, nervous, and what? Answer: reproductive systems

A: Organ system : Group of organs that work together to perform a certain function. Examples of organ systems in a human include the skeletal, nervous, and reproductive systems.
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Q: Question: What do bees do for flowering plants? Answer: pollinate

A: Thomas Quine (Flickr:quinet). Bees are important pollinators of flowering plants . CC BY 2.0.
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Q: Question: What is the force of attraction between things that have mass Answer: gravity

A:
Gravity has traditionally been defined as a force of attraction between things that have mass. The strength of gravity between two objects depends on their mass and their distance apart.
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