Yes, but that is not a good arguments. Example of unique living organisms include bacteria, tardigrades, or paramecia.

Yes, but none of those are of the human species. A Hunan zygote is a unique living human organism, and I think history has shown us we must at least be very, very careful when we start arguing that some unique living human organisms are different enough from the unique living human organisms that matter that it should be morally acceptable to kill them.

Maybe this really is different from all the things about which we've later lamented, "Never again!" but we certainly ought not consider that criterion easily satisfied.