@Mor - I hope he ended up with a decent nasal cycle as well. It's something that people don't notice at all until it doesn't work anymore. Basically it's just the tissue of each nostril getting an increased blood supply so that it produces more mucus. It swaps between nostrils, I assume, to make sure your nose doesn't get blocked.
Sounds gross, but it actually keeps your nose moist and able to process air properly, so it stops it from getting an infection and becoming much grosser.