english: It's not like your heart cells and kidney cells get all mixed up every day, and that's because there's all of this chemistry going on, these molecules that say who each of these groups of cells is and what their tasks should be.
non_english: Nije kao da se ćelije vašeg srca i bubrega pomešaju svakog dana, a to je sve zbog ove hemije, ovih molekula koji govore koja je tačno koja grupa ćelija, i koji je njihov zadatak.