Our skin is pretty incredible. It protects us and helps us sense the world around us. Some people have colored patches or dots on their skin called birthmarks. We wanted to know what birthmarks actually are, so we asked dermatologist Liz Farhat to help us find the answer.

Got a question that makes you say “holy MOLE-y!” Send it to us at BrainsOn.org/contact, and we’ll help spot the answer.

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