There is a reason to hold a seemingly dichotomous position regarding embryonic life and easing restrictions in special cases. We are also in a battle to protect embryonic life from experimental exploitation. By acknowledging that embryonic life is to be protected from murder with the exceptions clearly stated, the problem of supporting the life of embryonic humans is more tenable.
I don't know. Every source seems to make a different claim. I have childcare books that claim the heart begins beating between 5-6 weeks of pregnancy... which would fall around a month and a half after conception. In fact, the booklet from which I take that number contains the very photos in the article that started this thread. Even at 15 days, though, it's hard to argue against a heartbeat.