life starts before conception. SPerm is alive, eggs are alive, the parents are alive(hopefully)
The question is, what cells matter?
you don't give a fuck about blood, skin, or any other random cell.
So why do you care about embryo's? The body flushes out unfertilized AND fertilized eggs naturally. Sometimes, during pregnancies the body rejects, and absorbs the fetus.
You don't care about sperm, or eggs. But somehow it magically different the moment its fertilized? bullshit.
Let me ask you, on the other end.
Terry Schrivo. Would you have cut off her life support?
She was brain dead. If you agree she was DEAD, and it as just her body hanging on as a complicated system that can carry on past death of the brain. then the same applies at gestation. the fetus must develop as simple tissue, and masses of cells, that develop into a body. But until the brain is up and functioning, its not a person, its just a developing body.
I'm not going to pretend we know exactly when that occurs.. but its certainly enough to allow for early term abortions.
Tissue cultures, skin grafts, etc. Cloning. no brain. not a person.