Bees contribute to pollination by transferring pollen from the male part of a flower to the female part, which fertilizes the plant and allows it to produce seeds or fruits. Bees are attracted to flowers for their nectar and pollen, and as they collect these resources, they inadvertently brush against the flower's reproductive structures, picking up and depositing pollen as they move from flower to flower. This process is essential for the reproduction of many plant species and helps in the production of fruits, vegetables, and seeds.