Answer:
The zygote
Step-by-step explanation:
I'm not exactly sure what you're talking about, but this is what I found: "Every cell in the body originates from a single fertilized egg called a zygote. The zygote divides repeatedly to produce an embryo. These embryonic cells continue to divide, differentiating into all the cell types present in the body of all humans (and other mammals), from a new-born baby to an elderly adult."