BOW Double Fertilization

Double fertilization occurs in flowering plants. These flowering plants are also called angiosperms. The double fertilization process involves the joining of a female gametophyte with two male gametes. The male gametes are also known as sperm. This process begins with a pollen grain which sticks to the stigma of the carpel. The carpel is the female reproductive structure of a flower. Moisture adds to this process and helps the pollen grain germinated. Later this forms a pollen tube that stretches down toward the ovary through the style. The micropyle opening in the ovule is penetrated by the tipe of the pollen tube. It now is able to enter the ovary. The pollen tube can now let the two sperms go in to the megagametophyte. While the egg is being fertilized by one sperm, another sperm is used to combine the two polar nuclei of the central cell of the megagametophyte. The haploid sperm cell combines with the haploid egg to create a diploid zygote. The polar nuclei that contributes to the endosperm comes from mitosis from the same meiotic product that created the egg.

Sources:
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