Sokolowski – cell differentiation

So all the cells in our body have the same DNA compliment, and any individual arises from one sperm and one egg, and all the cells have the same DNA except for sperm and egg that have half. And so one question is: how is it that we end up differentiating how is it that some of our cells end up as liver, some as kidney, some as brain: And this has to do with how the environment around the cell talks to the DNA in that cell. So some of the DNA for some of the genes gets expressed- when you’re making a liver cell, and other genes get expressed when you’re making, for instance, a brain cell, so that’s within an individual how there’s differences in gene expression that give rise to different kinds of cells. The DNA is the same in all cells but the gene expression, the proteins that are made are different.