Citation, Please?
LOL, try a junior high school biology book. I've seen obtuse but you take the cake.
Child's play!
Take a look at this definition of "zygote." Note that this is part of a series called "Stages of human development." Care to guess what the first line of the "Stages of human development" article is?
Human development is the process of growing to maturity. In biological terms, this entails growth from a one-celled zygote to an adult human being.
Before you say that it's Wikipedia and doesn't count, consider the fact that Nature counts Wikipedia to be about as reliable as the Encyclopedia Brittanica on scientific issues Then try this on for size. As you may have guessed, it's a Google search on the phrase "human zygote" which returned 16,700 hits. Now, there are some pro-life sources (and pro-abortion sources) on that page, but note how many of them are non-political, and how many are serious scientific works. On the first page alone, you've got the Purdue biology department, a medical stock photo company (medicine is still a peer reviewed science, right?), the National Institutes of Health and the journal Human Reproduction.
Humans are human from the time of conception. That is scientific fact. Any law that ignores this idea is every bit as invalid as a law based on the Earth being flat.