I've heard these arguments before. I can only suggest you spend more time with this debate.

1. "religious Trojan horse"... I'm an atheist.

2. "An embryo IS..." both embryos and born humans are clumps of cells. I also don't claim to speak for the science-minded.

3. "An embryo can NOT..." your observation on fetal dependence applies acutely to infants as well. All humans depend on other humans to survive. This point generally isn't made anymore.

4. "parasite, or, in fact a tumor". biologically ignorant, and would apply to infants and children in any case.

5. "I could show you.." at a glance, probably not, but they are embryos of different species, and it wouldn't be hard to prove if you did more than glance at it. This point also isn't made anymore by knowledgeable pro-choicers.

6. Most people who live with mental illness or poverty still consider their own lives worth living.