Question

After pollen lands on the stigma, it grows a pollen tube down the style and to the bottom of the ovary, where the pollen the divides to produce sperm. The sperm then swim into the ovary and unite with an egg. This union of sperm and egg is_______

Answer 1

The union of sperm and egg after the growth of a pollen tube in flowering plants is known as double fertilization, resulting in a diploid zygote and triploid endosperm.

Step-by-step explanation:

After pollen lands on the stigma of a plant, it grows a pollen tube down the style to the ovary, where the generative cell within the pollen divides to produce two sperm cells. The process of a sperm uniting with an egg is known as fertilization.

Specifically, the union of sperm and egg in flowering plants leads to double fertilization where one sperm fertilizes the egg, creating a diploid zygote, and the other sperm fuses with two polar nuclei to form a triploid cell that will develop into the endosperm. This unique process of double fertilization results in the formation of the seed and eventually the fruit of the plant.