If DNA is identical in all cells of a living organism, what makes some cells become specialized?


I understand that my DNA is what defines me, what makes me me.
However, why do some cells become skin cells, others become hair cells, others gut?

In: Biology

Cell differentiation is also coded for in genes. As an embryo grows the stem cells divide next to other cells who send chemical messages that say “you’re in the heart, so you better become a heart cell or we’llboot you out”.

Imagine having a recipe book but each specialized cell only uses one recipe. To get what you need done you only do a hand full of recipes but you have them all in a book

Certain cells turn off parts of the dna or activate others. The information to everything is in every cell but not every cell uses everything.