Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Scientists may publish articles about their research in peer-reviewed science journals. Peer review means that the work is analyzed by peers, in other words, by other scientists. The articles are published only if the other scientists are convinced that the research is accurate and honest. Answer: peer review

A: What is the process where scientific articles are checked and analyzed by other scientists before publication?
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Q: Passage: Bacteria can be used to make cheese from milk. The bacteria turn the milk sugars into lactic acid. The acid is what causes the milk to curdle to form cheese. Bacteria are also involved in producing other foods. Yogurt is made by using bacteria to ferment milk ( Figure below ). Fermenting cabbage with bacteria produces sauerkraut. Answer: lactic acid

A: Bacteria can be used to make cheese from milk. the bacteria turn the milk sugars into what?
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Q: Passage: Every moment of every day is a field trip to gravity. Gravity is everywhere! You have a gravitational attraction to your dog. You have one to your pencil. You even have one to your school principal! These gravitational attractions are very small compared with the most important one you have. This is your gravitational attraction to Earth. It's what keeps you from floating off into space. Gravity holds our planet together. Gravity keeps Earth orbiting the Sun. We wouldn't be here without gravity. Answer: gravity

A:
What keeps the earth orbiting the sun?
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