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

Q: Passage: The rock of the mantle is mostly peridotite. Peridotite is formed of crystals of olivine (green) and pyroxene (black). Answer: peridotite

A: The rock of the mantle is mostly what?
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Q: Passage: Identify evidence for electroweak unification. The quarks in a particle are confined, meaning individual quarks cannot be directly observed. Are gluons confined as well? Explain. Answer: directly observed

A: The quarks in a particle are confined, meaning individual quarks cannot be what?
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Q: Passage: When was the last time you enjoyed yogurt on your breakfast cereal, or had a tetanus shot? These experiences may appear unconnected, but both relate to bacteria which do not use oxygen to make ATP. In fact, tetanus bacteria cannot survive if oxygen is present. However, Lactobacillus acidophilus (bacteria which make yogurt) and Clostridium tetani (bacteria which cause tetanus or lockjaw) share with nearly all organisms the first stage of cellular respiration, glycolysis ( Figure below ). Because glycolysis is universal, whereas aerobic (oxygen-requiring) cellular respiration is not, most biologists consider it to be the most fundamental and primitive pathway for making ATP. Answer: glycolysis

A:
What is the first stage of cellular respiration called?
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