In fact, the cells get smaller and smaller. But these cells are identical. They carry the same exact genetic information and they are of equal size. So what exactly is the purpose of cleavage? Well, the purpose of cleavage is to actually partition that zygote into many identical cells so that we can use these identical cells later on as the building blocks to actually form that developing embryo and eventually form that organism, the adult organism. So this is the process of cleavage.