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  2. Aquatic respiration - Wikipedia

    en.wikipedia.org/wiki/Aquatic_respiration

    Some species of sharks use this system. When they swim, water flows into the mouth and across the gills. Because these sharks rely on this technique, they must keep swimming in order to respire. Bony fish use countercurrent flow to maximize the intake of oxygen that can diffuse through the gill. Countercurrent flow occurs when deoxygenated ...

  3. Physiology of underwater diving - Wikipedia

    en.wikipedia.org/wiki/Physiology_of_underwater...

    The oxygen affinity of the blood is related to lung volume. Where the lungs do not represent an oxygen store, the oxygen affinity is low to maximise the unloading of oxygen and to maintain a high tissue oxygen tension. Where the lungs are utilised as an oxygen store, the affinity is high and maximises uptake of oxygen from the alveolar volume. [13]

  4. Human physiology of underwater diving - Wikipedia

    en.wikipedia.org/wiki/Human_physiology_of...

    In humans, about a third of every resting breath has no change in oxygen and carbon dioxide levels. Dead space in a breathing apparatus is space in the apparatus in which the breathing gas must flow in both directions as the user breathes in and out, increasing the necessary respiratory effort to get the same amount of usable air or breathing ...

  5. How Long Can Humans Hold Their Breath?

    www.aol.com/news/long-humans-hold-breath...

    Humans set breath-holding records in water because they "can hold their breath twice as long underwater they can on land." The world record is 19 minutes and 30 seconds. It depends--but you can ...

  6. Oceanic physical-biological process - Wikipedia

    en.wikipedia.org/wiki/Oceanic_physical...

    Water forms the ocean, produces the high density fluid environment and greatly affects the oceanic organisms. Sea water produces buoyancy and provides support for plants and animals. That's the reason why in the ocean organisms can be that huge like the blue whale and macrophytes. And the densities or rigidities of the oceanic organisms are ...

  7. Marine biogeochemical cycles - Wikipedia

    en.wikipedia.org/wiki/Marine_biogeochemical_cycles

    The word oxygen in the literature typically refers to molecular oxygen (O 2) since it is the common product or reactant of many biogeochemical redox reactions within the cycle. [37] Processes within the oxygen cycle are considered to be biological or geological and are evaluated as either a source (O 2 production) or sink (O 2 consumption). [36 ...

  8. Oxygen minimum zone - Wikipedia

    en.wikipedia.org/wiki/Oxygen_minimum_zone

    In OMZs oxygen concentration drops to levels <10 nM at the base of the oxycline and can remain anoxic for over 700 m depth. [7] This lack of oxygen can be reinforced or increased due to physical processes changing oxygen supply such as eddy-driven advection, [7] sluggish ventilation, [8] increases in ocean stratification, and increases in ocean temperature which reduces oxygen solubility.

  9. Marine chemistry - Wikipedia

    en.wikipedia.org/wiki/Marine_chemistry

    The map indicates coastal sites where oxygen levels have declined to less than 2 mg/L (red dots), as well as expanding ocean oxygen minimum zones at 300 metres (blue shaded regions). [27] Ocean deoxygenation is the reduction of the oxygen content in different parts of the ocean due to human activities. [28] [29] There are two areas where this ...