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Oxygen enters seawater primarily through diffusion from the atmosphere at the ocean's surface. This process allows oxygen to dissolve in the surface waters, where it can be used by marine organisms for respiration. Ocean mixing and circulation also help distribute oxygen throughout different depths of the seawater column.
oxygen \
Hydrogen, oxygen, trace minerals.
oxygen \
Fish and marine life are able to live because oxygen is soluble in water, including salt water/seawater.
There is more oxygen in seawater. Seawater contains around 5 to 10 milligrams of oxygen per liter, while the concentration of oxygen in the air is about 210 milligrams per liter. However, the total amount of oxygen in the oceans is much higher due to their vast volume.
Seawater and fresh water contains oxygen that fish absorb using their gill. So the substance is oxygen.
Two sources of oxygen in seawater at the surface include atmospheric exchange, where oxygen from the air dissolves into the water, and photosynthesis by marine plants and phytoplankton, which produce oxygen as a byproduct.
Oxygen enters seawater through diffusion from the atmosphere at the water's surface and through photosynthesis carried out by marine plants and phytoplankton.
Marine organisms extract dissolved oxygen from seawater through their gills, lungs, or skin. These structures have respiratory surfaces with a large surface area, allowing for efficient exchange of oxygen and carbon dioxide with the surrounding water. Oxygen diffuses from the seawater into the organism's respiratory surface and is then transported to the cells for cellular respiration.
Dissolved salts are transported by the rivers.
Oxygen enter the capillaries by diffusion due to difference in oxygen concentrations.