Quick! Name your five favorite smells. Ours are old books, the smell of rain, freshly brewed coffee, literally any baked good ever, and leather. If you’re guessing that we’re about to school you on your schnozz, then you’re absolutely correct. Let’s get into it.
Your noses will both rise and fall during the course of your life. It sounds terrifying, but it isn’t, we promise. By your late teens, your nose has reached its final form, but this is before gravity and time have had their way with your sniffer. As you grow older your nose will begin to sag and lengthen.
Do you have a unique sneeze style? A sneeze begins with an irritant and then is detected by the trigeminal nerve which causes reflexes that are just trying to expel the irritant; a deep inhalation followed by the closing of the glottis in the throat and a buildup of pressure in the lungs (“ah”), then the sudden opening of the glottis as the diaphragm forces air up through the mouth and nose, expelling the irritant (“choo!”) But not everybody’s sneeze sounds like your classic “ah-choo” now does it? Sneezes are a neurological reflex we’re all born with which is why no matter what a sneeze sounds like as it’s coming out, yours is probably very similar to that of your family’s.
There is a lot of mucus in a single nose. While you more than likely don’t notice it, your nose produces roughly one liter of mucus each day. Luckily it’s not just a stream running down our face, in fact, most of it runs down our throat thanks to post-nasal drip.
Have you ever wondered exactly how you smell something? Take for instance freshly brewed coffee. The coffee molecules enter your nose and waft over a patch of olfactory sensors on the ceiling of your nasal cavity, where they activate finger-like receptors that transmit chemical signals up to a central processor in your brain called the olfactory bulb, which registers the scent. Now, humans can detect around 10,000 scents, but that’s nothin’ compared to bloodhounds which have about 4 billion olfactory sensors, and bears which have seven times the scent of a bloodhound.
While we can smell a lot of smells, natural gas is not one of them. And considering natural gas is what heats our homes and how most of us cook, not being able to smell natural gas could be lethal. Because of this gas companies had to add the compound mercaptan to give gas an aroma.