"Embryos are not human beings, they're just human embryos." Clever bit of dissembling there snowy. In point of fact, you lived through your embryo age in order to reach the age you are now. When in the embryo age, you were a complete alive human ORGANISM. Did you have a brain then? No, not at the earliest ages you lived through, but your DNA instruction map functioned as a brain, sort of, until you built your brain (and you added onto that initial brain even well into infancy). You built for your survival the placenta you used, the umbilicus you received life support through, and the body of organs and tissues you exited the womb in. In fact, you, as an alive individual organism, built your parts before they took on function, yet it was the individual you were conceived as that did the work to sustain you in the water world of your Mother's womb and then to sustain you in the air world you enjoy today.
One thing I've sometimes wondered: if one were to put some sort of physical (not genetically reproduceable) marker on the chromosomes of a mouse zygote, where would those chromosomes end up? It seems to be that early gestational development serves to build a 'scaffold' within which the 'real' organism will develop. Although the scaffolding shares the same genetic code as the developing organism within, they are separate and distinct entities which separate from each other at birth.