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During pollination, this generative cell divides and gives rise to sperm cells. The female counterpart to the antheridium in cryptogams is the archegonium, and in flowering plants is the gynoecium. An antheridium typically consists of sterile cells and spermatogenous tissue. The sterile cells may form a central support structure or surround the ...
An immobile egg, contained in the archegonium, fuses with a mobile sperm, released from an antheridium. The resulting zygote is either male or female. A male zygote develops by mitosis into a microsporophyte, which at maturity produces one or more microsporangia. Microspores develop within the microsporangium by meiosis.
The corresponding male organ is called the antheridium. The archegonium has a long neck canal or venter and a swollen base. The archegonium has a long neck canal or venter and a swollen base. Archegonia are typically located on the surface of the plant thallus , although in the hornworts they are embedded.
For example, the oomycete antheridium is a syncytium with many sperm nuclei and fertilization occurs via fertilization tubes growing from the antheridium and making contact with the egg cells. Antheridia are common in the gametophytes in "lower" plants such as bryophytes , ferns , cycads and ginkgo .
Sperm are flagellated and must swim from the antheridia that produce them to archegonia which may be on a different plant. Arthropods can assist in transfer of sperm. [14] Fertilized eggs become zygotes, which develop into sporophyte embryos inside the archegonia. Mature sporophytes remain attached to the gametophyte.
Once the sperm has matured, the sperm requires water, such as raindrops, to help carry the sperm from an antheridium to an egg located in an archegonium on a female gametophyte shoot. The perigonium structure is composed of an antheridium, paraphyses (sterile filaments that support the reproductive structure of bryophytes), [14] and perigonial ...
As it approaches a mate, a haploid sac fungus develops one of two complementary organs, a "female" ascogonium or a "male" antheridium. These organs resemble gametangia except that they contain only nuclei. A bridge, the trichogyne forms, that provides a passage
The gametophytes produce both motile sperm in the antheridia and egg cells in separate archegonia. After rains or when dew deposits a film of water, the motile sperm are splashed away from the antheridia, which are normally produced on the top side of the thallus, and swim in the film of water to the antheridia where they fertilize the egg.