The amount of monitoring and adjusting that goes on in the human body at any given time is astounding. Thankfully, it's automatic, so you never have to think about it. In this interactive feature, however, every change in activity requires you to make adjustments in respiration or heart rate or energy delivery, and an adjustment to one system often changes the balance in some other system. See if you can do as good a job maintaining the harmony in this virtual body as your nervous system does in you.
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