It all occurs with such a natural occurrence that more often than not, you would not even notice. Your body was straining to remain in balance. A balanced state is the only one your body understands or even likes, and it would go to great lengths to be able to stay that way. Sodium, sugar, blood pressure, temperature, heart rate and even your breathing are just some of the things it likes to keep in harmony. Have you ever wondered just how it goes about accomplishing this task? Where are the sensors, receptors and control switches located? What magical algorithm does your body use to know what is a balanced state and what it needs to stay that way?
One of the famous actors on this stage is called a chemoreceptor. Located on the common carotid artery, they are a cluster of cells that play the role of sensory detection. They are capable of sensing minor fluctuations in the chemical composition in your blood. Packed with neurotransmitters, they then signal these changes to your brain or more specifically your medulla. The response from the brain can then trigger a physical response that will make your body adapt to the change in the chemical composition of your blood. Imagine that you are not getting sufficient oxygen. Your brain will trigger your lungs to breathe in more deeply to ensure that you get the oxygen you need. In nothing short of a miracle, if you are oxygen deprived, your chemoreceptors might even swell in size and increase their numbers to ensure that the signals are amplified sufficiently to your brain.
A significant number of these activities occur without any great effort on your part of perhaps even you noticing. It is only when your response gets acute, say you start shivering uncontrollably because your temperature dropped that you might realise something is amiss. Till then, chemoreceptors keep on doing their task, and you didn’t even know their name.