In this task, you need to write a topic word from the given fact. The topic word must have at least one word overlap with the given fact. The topic word often involves adding a new word from a related concept. In your topic word, use at least one word from the given fact. Topic words with two or more words work best.
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Question: Fact: Viruses are not cells.

Answer: Viruses.


Question: Fact: transpiration is when water vapor moves from plants into the atmosphere.

Answer: atmosphere air.


Question: Fact: Gene flow occurs when individuals move into or out of a population.

Answer:
Gene flow.