Final answer:
The zygote is formed through the fertilization of an egg by a sperm. Mitosis is the process by which the zygote undergoes cell division and develops into an embryo. The genetic instructions for this process are found in the zygote's DNA.
Step-by-step explanation:
The zygote is formed when a sperm fertilizes an egg. It is a one-cell structure that undergoes cell division called mitosis. Mitosis is the process by which the zygote divides and multiplies, forming more specialized cells as it develops into an embryo. The instructions that guide this process are found in the genetic information carried by the zygote's DNA.