Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Oxygen is needed to make ozone. Ozone is a molecule made of three oxygen ions. Ozone in the upper atmosphere blocks harmful solar radiation from reaching the surface. Without oxygen, life on Earth would have been very simple. Answer: three

Answer: How many oxygen ions make up an ozone molecule?

Question: Passage: Neurons that innervate the muscles of the respiratory system are responsible for controlling and regulating pulmonary ventilation. The major brain centers involved in pulmonary ventilation are the medulla oblongata and the pontine respiratory group (Figure 22.20). Answer: neurons

Answer: What basic structures of the nervous system innervate the muscles of the respiratory system and are responsible for controlling and regulating pulmonary ventilation?

Question: Passage: Beginning in puberty, each month one of the follicles and its primary oocyte starts to mature (also see Figure below ). The primary oocyte resumes meiosis and divides to form a secondary oocyte and a smaller cell, called a polar body. Both the secondary oocyte and polar body are haploid cells. The secondary oocyte has most of the cytoplasm from the original cell and is much larger than the polar body. Answer: cytoplasm

Answer:
What does the secondary oocyte have the most of from the original cell?