Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: The pioneer species is soon replaced by other populations. Abiotic factors such as soil quality, water, and climate will determine the species that continue the process of succession. Mosses and grasses will be able to grow in the newly created soil. During early succession, plant species like grasses that grow and reproduce quickly will take over the landscape. Over time, these plants improve the soil and a few shrubs can begin to grow. Slowly, the shrubs are replaced by small trees. Small trees then are succeeded by larger trees. Since trees are more successful at competing for resources than shrubs and grasses, a forest may be the end result of primary succession. Answer: primary succession

Answer: What's the term for the gradual progression from simple plants to larger more complex ones in an area?

Question: Passage: According to the table, aluminum has an atomic number of 13. Therefore, every aluminum atom has 13 protons in its nucleus. Iron has an atomic number of 26. Therefore, every iron atom has 26 protons in its nucleus. Carbon has an atomic number of 6. Therefore, every carbon atom has 6 protons in its nucleus. Saylor URL: http://www. saylor. org/books. Answer: nucleus

Answer: According to the table, aluminum has an atomic number of 13. therefore, every aluminum atom has 13 protons in its what?

Question: Passage: Plants maintain the atmosphere. They produce oxygen and absorb carbon dioxide during photosynthesis. Oxygen is essential for cellular respiration for all aerobic organisms. It also maintains the ozone layer that helps protect Earth's life from damaging UV radiation. Removal of carbon dioxide from the atmosphere reduces the greenhouse effect and global warming. Answer: uv radiation

Answer:
The ozone layer protects the earth from what?