The electric field of a charge is defined by the force on what kind of particle?

I am not positive, but it is either a electron, a proton, a source charge, or a probe charge. I am not positive. You will have to go with your best instincts.

cell differentiation  is how generic embryonic  cells  become specialized  cells. this occurs  through a process called gene expression. gene expression is the specific combination of genes that are turned on or off (expressed or repressed), and this is what dictates how a  cell  functions.

explanation:

come closer and become far apart and become steam/gas