system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How come you can't really taste the food that's in your mouth if you don't breathe through your nose?
gpt
Much of what we think of as taste is really smell.  Your tongue can only sense a small number of flavours (salt, sweet, bitter, sour, umami and perhaps fat) but your nose can sense hundreds of smells.