Comments by "" (@dustintacohands1107) on "Titanic submarine's fatal implosion likely heard on US Navy’s secret acoustic system" video.

@OffendingTheOffendable The mammalian dive reflex is four things. Your heart rate slows down, which reduces the rate of oxygen entering your bloodstream, allowing your vital organs to use it more efficiently. Your blood vessels contract, directing blood flow away from your extremities so that you’re not wasting precious oxygen on dumb things like fingers and toes. Since the lungs (and the air in them) compress as you dive deeper, the blood that moves from your extremities into your chest cavity is necessary not only for keeping the important stuff functioning properly, but also to keep your lungs from collapsing. Next the splenic contraction. Since your spleen is relatively large and full of blood, it (very unselfishly) squeezes all that blood into the circulatory system, which, of course, adds more oxygen into the mix.
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