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

Q: Passage: Although lots of symbiotic relationships help both organisms, sometimes one of the organisms is harmed. When that happens, the organism that benefits, and is not harmed, is called a parasite . This type of relationship is known as parasitism. Answer: parasite

A: Although lots of symbiotic relationships help both organisms, sometimes one of the organisms is harmed. when that happens, the organism that benefits, and is not harmed, is called a what?
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Q: Passage: Light moving from air into water is bent ___________ the normal. Answer: more

A: Light moving from air into water is bent ___________ the normal?
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Q: Passage: Arteries are muscular blood vessels that carry blood away from the heart. They have thick walls that can withstand the pressure of blood being pumped by the heart. Arteries generally carry oxygen-rich blood. The largest artery is the aorta , which receives blood directly from the heart. Answer: aorta

A:
What is the largest artery in the body called?
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