Asked by Janet Taylor
The body does much more than remembering to breathe; it has a finely tuned mechanism that controls how we breathe, depending on how much oxygen we need. Chemical sensors check the amount of oxygen and carbon dioxide in the blood. Parts of the brain generate a pattern for breathing in and out, which changes depending on our needs. If there’s too much carbon dioxide in the blood, we breathe faster and deeper. We even have receptors that sense how much our lung tissue is stretching, for very precise control.
If we really want to control our breathing, the brain cortex takes over and that’s when we are conscious of the whole process. There are any other things that our body does automatically with a manual override, such as walking on two feet or riding a bike without losing our balance.
Answered by José Monteiro, Science Museum