Pollen is a powder that contains microgametophytes that then produce sperm cells. Pollen grins generally have a hard coat that protects the sperm, and contains many different types of cells. The vegetative cells produce the pollen tube and generative cells produce the sperm cells. Pollen is produced in the anther of flowering plants or the male cone of a coniferous plant. In a flowering plant, the pollen is then passed to the pistil through pollination. A pollen tube descends into the ovary, where the sperm cells can fertilize the ovules.