After the fertilization of the male and female gamets of the plant in the ovary the egg cell present in the ovary combines with a sperm cell present in pollen grain and form the zygote.After this the ovules in the ovary starts developing into a seed and the ovary into fruit which takes sometime.In the meanwhile the zygote divides into number of cells and form the zygote.So,a seed has an embryo and not a zygote.
