how do some calls become brain cells and other become skin cells, when the DNA in ALL the cells is exactly the same. In other words, if the instructions are exactly the same, how does one become a brain cell and another a skin cell?

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this