Ronan O’Rahilly is an embryologist. Pro-life author Rick Garrett describes him this way:
“Ronan O’Rahilly is the human embryologist who developed the classic Carnegie stages of human embryological development. He also sits on the international board of Nomina Embryologica (which determines the correct terminology to be used in human embryology textbooks).”
According to O’Rahilly:
“the fusion of the sperm (with 23 chromosomes) and the oocyte (with 23 chromosomes) at fertilization results in a live human being, a single-cell human zygote, with 46 chromosomes – the number of chromosomes characteristic of an individual member of the human species, not a blob of cells that are part of the mother’s body.”