Now that the videos which the anti-choice idiots were debunked so thoroughly, the goal posts have been shifted. Not a big surprise, but the new posts are so easy to debunk it's pathetic.
They claim "human lives" are killed by abortion, but getting them to define "human life" offers fuel for mockery. Often they will define it as "a living organism with human DNA," which actually includes sperm, every organ, eggs, and even tumors.
Tumors are the key to this, they are a parasitic organism, by definition, which is made up of human DNA, specifically the DNA of the one suffering from them. In essence, the tumor is exactly like the fetus, the fetus only develops to a stage that allows it to, eventually, become self reliant and sentient.
Scientifically, every cell is a living organism, even the cells in a tumor. So they are forced to redefine what life is, often they will jump to life being sentient. The vast majority of life on Earth is not sentient, viruses and bacteria still dominate the planet.
Sentience does not begin until the brain begins recording and processing the surrounding world. It does not actually appear fully sentient for several months in humans.
Yes, the brain is where we actually are, every cell in the body is it's own organism, but the individual is the collective responses of the brain. The heart is just another colony of living organisms, symbiotic association to the rest of the body.
Each organ is a colony of single celled animals working together, symbiotically working with all other organs. The brain is the most vital organ, it is you, the rest can be replaced without killing you.
This throws a monkey wrench into the entire anti-choice platform, reducing them to religious claims and pseudoscience. So yes, abortion is killing it is not murder, but it is no different than removing any other organ that becomes parasitic.