Double Fertilization evolved in flowering plants or angiosperms. The process involves the coming together of a a female gametophyte with to male gametes. It all starts when a pollen grain lands on the stigma of he carpel, which is the female reproductive structure of a flower. The grain of pollen takes in the moisture and begins to germinate. It forms a pollen tube that extends down to the ovary through the style. The tip of the pollen tube enters the ovary and opens the ovule and releases two sperms. One sperm will fertilize the egg and the other sperm will combine with the two polar nuclei. A diploid zygote will form. The large cell will begin to develop into the endosperm. This will help the embryo develop. Then the ovary will develop into a fruit which holds the nutrients and protects it.
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