One of the two male gametes formed in the pollen tube of gymnosperms after mitotic division of the * body cell. In some species, e.g. Cycas and Ginkgo, they are flagellate and swim from the pollen tube to the archegonia. Such antherozoids, in contrast to the nonmotile * generative nuclei of angiosperms, are associated with a large amount of cytoplasm and in Cycas reach a diameter of 300 μη. In other gymnosperms, e.g. the Gnetales and Coniferales, the sperm cells are not motile. The term sperm cell is sometimes applied to generative nuclei. |
