In my latest feature for The Scientist Magazine, I wrote about how sensory receptors — the light, taste, and odor receptors that are primarily present in our eyes, tongues, and nose — are present all over the body, and have all kinds of functions. 

It turns out taste receptors in the gut and airway influence some of the earliest immune responses to bacteria and parasites, and your ability to taste bitter substances could influence how prone you are to respiratory infections. 

Also, blood vessels relax in response to light, and odor receptors in the kidney regulate blood pressure in response to fatty acids produced by gut bacteria, providing a means by which diet could directly affect blood pressure. Other odor receptors could affect how prone muscles are to injuries, how quickly skin wounds heal, and how sperm find their way to the egg.

Check out the full article here, and here are some illustrations for it.