Just opened a new bottle of Dr Pepper a bit close to my right nostril and breathed in just as the carbon dioxide part of it decided to fizz.
I felt the gassy part of it go right up my right nostril, go through a small tube at the back of my nose and down to the back of my throat where it stopped and I burped!
Yes, I had biology lessons at school as a kid but it was all text books and occasional video's. Today was my first practical human biology lesson! lol