Don't worry if the early blooms on these plants fall off before setting any fruit. Cucumbers and squash often produce many male flowers that bloom and die before the female blossoms appear. The female blossoms have what looks like a tiny squash or cucumber below the flower. The tiny fruit is the ovary, full of eggs not yet fertilized via pollen from male flowers. Male blossoms have long stalked stamens, each with pollen-filled anthers.
Every pollen grain contains sperm nuclei, which fertilize the ovules in the female flowers.
Visiting bees and other types of insects provide the transportation - when they visit flowers to collect nectar and pollen, bees carry and spread the male pollen from male anthers to female pistils. Each pollen grain grows a long tube down through the pistil, to the egg cells. The sperm nuclei migrate down the tube to the egg, where fertilization takes place. The fertilized eggs, now the seeds, and surrounding ovary will eventually grow into a huge squash or cucumber. Inside, each seed is a tiny plant embryo, the product of the union of an egg and sperm.