Question: what is the difference between a human zygote?
Answer: "Zygote: This cell results from the union of an oocyte and a sperm. A zygote is the beginning of a new human being (i.e., an embryo). The expression fertilized ovum refers to a secondary oocyte that is impregnated by a sperm; when fertilization is complete, the oocyte becomes a zygote."10 (Emphasis added.)