There are a couple problems with your argument.
First, in the abstract I can agree with definition one and definition two, but only by using a slightly different definition of "human being" each time. If you insist on having a consistent definition, then you have to display it and I'm sure I'll disagree with one or the other of those statements. Your #2 definition involves genetics. Your #1 definition involves moral culpability and is unrelated to genetics.
The second problem is that just because the unborn have the right to live which should be protected by law, it does not imply that abortions should be illegal. Otherwise this logic would hold:
IF: 1. Every human being has the right to live, which should be protected by law,
AND: 2. The person brutally assaulting your family is a human being.
THEN: 3. The person brutally assaulting your family has the right to live, which should be protected by law.
I agree with both premises and even the conclusion, but if you kill somebody in self defense or in the defense of another, it's not murder.
Likewise, nobody ever argues that any human being *other than a fetus* gets to attach themselves in a biologically parasitical fashion to another human being for months at a time. Why do the unborn get this special right that nobody else gets?
Call me when you make a Star Trek transporter that can zap a fetus out of the womb and into an incubator and we can ban abortions at that time, since then the fetus doesn't need a special right to remain inside somebody else's body.