We take our snot for granted, but it's actually a really important substance that keeps our noses (and lungs and even our digestive system!) working smoothly. This video gives the lowdown on those occasionally green blobs
The colour of snot varies, turning green when we're sick because of a greenish enzyme called myeloperoxidase. And it gets thicker because it's full of living and dead immune cells.
Check out the video for more facts about this slimy substance.
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