The correct answer is - cyanobacteria.
The atmospheric oxygen came from the cyanobacteria. These were one of the earliest living organisms on Earth. The cyanobacteria was using photosynthesis in order to create its own food. The photosynthesis process requires sunlight, carbon dioxide, water, and oxygen. The oxygen is mostly released as a waste product from the process of photosynthesis, thus the cyanobacteria were literally releasing oxygen that was ending up into the atmosphere. As more and more cyanobacteria there were across the planet, more and more oxygen they were releasing into the atmosphere, slowly changing the composition of the atmosphere, and setting the basis of it as we know it now.
Answer:
The Moon is significantly smaller than the Earth and so its core contained less energy to begin with and also cooled significantly faster. Thus, the Moon's core is relatively cool and solid, whereas a portion of the Earth's core is liquid.
Explanation:
The Gobi Desert spans across Mongolia and China. It specifically runs across northwestern and northern China and Southern Mongolia. The Gobi is a large desert region in Asia and is a rain shadow desert formed by the Himalaya range blocking rain-carrying clouds from the Indian Ocean from reaching the Gobi territory. The Gobi is most notable for it being the location for several important cities in the Silk Road and as part of the Great Mongol Empire.
The abiotic parts of an ecosystem are water, soil, air and dead organic matter. The correct options among all the options that are given in the question are the second, fourth, sixth and seventh options. They are basically non-living things that are present in the ecosystem. I hope it helps you.
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