Question: how do we know how to breathe????


  1. Super awesome question!
    Knowing how to breathe is an instinct that kicks in a birth, knowing when to breath is an automatic process that your body controls.
    Basically the amount of Carbon Dioxide, not Oxygen, is monitored in the blood. If the level of CO2 gets too high it is detected in the brain which then tells the lungs to move and you breath.
    A back-up mechanism looks samples the CO2 levels at other parts of the body such as in your elbows and knees and if it gets too high in these locations nerves tell your brain to tell your lungs to move.
    Finally there is a last ditch response that your body has called the oxygen baroreceptor override response. There are special cells in the arteries around the heart that detect the pressure of oxygen gas pushing on the artery wall. If this drops too low then nerves signal to the brain to ignore all other signals and move the lungs to help you breath. That is why when people start drowning they glup water, their body’s are forcing them to attempt to breath underwater.
    So, in conclusion. Brain checks CO2 and is control most of the time, if the brain stuffs up your knees will tell you to breath and if they stuff up as well the arteries around your heart will force you too.


  2. Hi Princess

    Thats a pretty good answer there from James, I might just add, that we know how to breath in the same way that after you have eaten your food, your body knows how to digest it.