Mold is a fungus, like mushrooms. And it's made up of thousands of threadlike filaments called hyphae. It uses those filaments like roots: to feed. Hyphae extend into your stale bread or rotten ...

The mold's only on part of the bread. So, I can just cut that away and ... But there's a vast network of subterranean "roots" called hyphae that you can't see. So let's take another look at ...