Cooled quickly, because lava cools and crystallizes rapidly
They all contain a gravitational pull that allows them to stay together and to keep objects within orbit
There is a loss of cultural diversity
Answer: Oxygen
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Respiration is the use of oxygen to produce energy. Oxygen, or

, is also created as a by-product of photosynthesis during the light-dependent reactions. The photolysis, or breaking down of water, H2O, during photosynthesis, created oxygen as a by-product.