Talk:Breathing/Archive 2

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‘Invention’ of breathing????
A highly dubious statement, without a reference. Breathing could not have evolved (or been ‘invented’) 3.44 billion years ago — the Great Oxygenation Event did not begin until 2.4 billion years ago! DrJonJ (talk) 23:21, 4 February 2020 (UTC)

Autonomous breathing
Fully autonomous breathing only takes place while sleeping. While awake, breathing is a conscious decision. Every breath takes place on demand. The breathing rate can be overriden by the brain to a certain extent during extenuating circumstances such as when exercising. — Preceding unsigned comment added by 92.21.15.48 (talk) 16:29, 26 February 2020 (UTC)

Composition
''The gas exhaled is 4% to 5% by volume of carbon dioxide, about a 100 fold increase over the inhaled amount. The volume of oxygen is reduced by a small amount, 4% to 5%, compared to the oxygen inhaled.''
 * This is wrong, or at least misleading: if inhaled air contains 21%, and exhaled air 13.6% to 16% oxygen, exhaled air contains 24% to 35% less oxygen than inhaled air (although that might confuse some readers. Perhaps "one fourth to one third less oxygen"?)
 * Also, because water vapor is included, the values listed under "typical composition" add up to more than 100%. Maybe it would be better to mention the water content elsewhere (not in the list) so the values add up to 100%. Prevalence  20:37, 27 November 2020 (UTC)