So it forms this two cell embryo stage where we have two identical cells. This process continues. We form four cells, eight cells, 16 cells, 32 cells and so on and so on until we form the billions of cells that are found inside the individual organism. So now in the stage of the zygote and the two cell embryo stage, these cells are said to be totipotent. And what that means is they have a great deal of potential and they can form any and all the cells that make up that adult human organism. Now, as the process of development continues, as the cells continue to divide and grow, their potential decreases and eventually their cellphate becomes determined.