I believe it is important because it is a biological marker for the potential of a separate human life starting. Before conception there is no potential for human life and thus no moral obligation to treat it as such. At that point it is just as valuable as your blood, saliva or other bodily fluids that bear your DNA.

The first bolded part is just not true except with a rather convoluted definition of potential, and the second one is just a new undefended claim.

Thanks for your explanations though. I will probably not respond further because in general I don't really care for the fetal personhood issue. I was really just disagreeing with your assertion that this was an easy issue.