In a flower, the filament is a long, thin stalk-like structure that supports the anther, which is the structure that produces pollen. The anther is generally borne at the tip of the filament. During the process of fertilization, pollen lands on the stigma, a tube grows down the style and enters the ovary. Male reproductive cells travel down the tube and join with the ovule, fertilizing it. The fertilized ovule becomes the seed, and the ovary becomes the fruit. The filament holds the anther up and gives support to it.