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

Q: Passage: The menstrual cycle includes events that take place in the ovary, such as ovulation. Answer: ovary

A: Ovulation takes place in what organ and is part of the menstrual cycle?
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Q: Passage: Greenhouse gases include CO 2 , H 2 O, methane, O 3 , nitrous oxides (NO and NO 2 ), and chlorofluorocarbons (CFCs). All are a normal part of the atmosphere except CFCs. The table below shows how each greenhouse gas naturally enters the atmosphere ( Table below ). Answer: greenhouse gases

A: Co 2 , h 2 o, methane, o 3 , nitrous oxides (no and no 2 ), and chlorofluorocarbons (cfcs) are known as what type of gases?
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Q: Passage: While the egg is developing, other changes are taking place in the uterus. It develops a thick lining that is full of tiny blood vessels. The lining prepares the uterus to receive a fertilized egg if fertilization actually takes place. Answer: tiny blood vessels

A:
While the egg is developing, other changes are taking place in the uterus. it develops a thick lining that is full of what?
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