The consensus is the formation of a zygote marks the beginning of a new individual human life.
So if a skin cell was human life, once it became a zygote it would be a new individual human life?
I don't think that's how it works.
Neither will a zygote. It needs a uterus, a placenta, an amnion, a chorion, a constant supply of blood from the mother to deliver nutrients and remove waste, a variety of hormones from the mother, warmth, physical protection, immunological protection, etc.
As I said before, it the potential to turn in to a human being at some point in the future given the right conditions is your baseline, then you can equally apply that reasoning to every single sperm or egg.
A born baby won't grow up and get a job without a mother, a constant supply of food&water and a warm enviroment.
So a zygote's going to do it as much as a born baby will.
In its natural condition, it will be born, if there isn't an intervention or an anomaly.
A skill cell will not be born in it's natural condition, it will just remain a skin cell.
I said that a person can be dead even if their heart is still beating and all their other organs are functioning, if their brain activity has ceased. Given that a fully grown adult without a functioning brain is no longer a human life, why would a fetus which doesn't even have a brain, let alone one which can function, be a human life?
The early signs of a brain have begun to form. Even though the fetus is now developing areas that will become specific sections of the brain, not until the end of week 5 and into week 6 (usually around forty to forty-three days) does the first electrical brain activity begin to occur
The neural tube, which becomes the brain and spinal cord, seals up completely three weeks after conception, one day after the fetal heart begins to beat. By the fourth post-conception week, the eyes and ears have started to form, including connections to the developing brain.
Ultrasounds may detect the first fetal movements as early as five weeks post-conception. These movements provide evidence of electrical impulses at the connection between nerves and muscles. In the sixth week, the forebrain – the brain region responsible for processing perception, thoughts, and decisions in adults – doubles in size. In fact, the brain starts growing at a rate of 250,000 neurons per minute for the next 21 weeks! In the seventh week, the fetus starts showing a preference for his right or left hand. By 11 weeks post-conception, the fetus performs complex behaviors that require working neural circuits, including hiccupping, stretching, grasping objects, and turning away from loud noises.
Importantly, the formation of the human brain dominates early development. In fact, at eight weeks post-conception, the fetal brain weighs 43 percent of its total body weight. By comparison, a newborn’s brain weighs 10 percent of his total body weight, and an adult’s brain weighs just 2 percent of his total body weight. Therefore, even early fetal development occurs in connection with neural activity.
Where do you draw the line?