How do living organisms obtain oxygen?

May 6, 2005 ... What climate factors influence the ratio of oxygen isotopes in ocean water? Evaporation and condensation are the two processes that most ... As plants became firmly established on land, life once again had a major effect on Earth's atmosphere during the Carboniferous Period. Oxygen made up 20 percent ... Oct 23, 2023 ... ... oxygen-poor blood to the lungs. It normally does this 60 to 100 times a minute, 24 hours a day. The heart is made of four chambers: The ... Scientists think the air was mostly made out of volcanic gases like carbon dioxide. So how did the oxygen get there? Archaen illustration. Where did Earth's ... What is the atmosphere of Earth made of? Earth's atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide with very small percentages of ... O2 is not an element, but a molecule made up of two oxygen atoms. These two atoms are chemically bonded together to form O2. What is the symbol of oxygen? Oct 19, 2023 ... Earth's atmosphere is composed of about 78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, and 0.1 percent other gases. Dissolved oxygen refers to the level of free oxygen present in water. Levels that are too high or too low can harm aquatic life and affect water quality. Mar 28, 2022 ... Today much of the oxygen in the atmosphere comes from photosynthesis in microorganisms, including the cyanobacteria, and the recently discovered ... May 8, 2013 ... Measurements of oxygen concentrations produced by the concentrators at defined temperatures and ambient relative humidity were made by the ...