A gametangium (plural: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. In contrast to gametogenesis in animals, a gametangium is a haploid structure and formation of gametes does not involve meiosis. In biology, an organ (Latin: organum, instrument, tool) is a group of tissues that perform a specific function or group of functions. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ... A gamete is a specialized germ cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... Typical phyla Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: ) are a diverse group of organisms, comprising those eukaryotes that are not animals... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Deuteromycota Fungi (singular fungus) are a kingdom of eukaryotic organisms. ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) †Rhyniophyta - rhyniophytes †Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses †Trimerophytophyta - trimerophytes Pteridophyta - ferns and horsetails Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... Gametogenesis is the creation of gametes by meiotic division of gametocytes into various gametes. ... Digimon, the only known animals. ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... Not to be confused with miosis. ...

Types of gametangia

Depending on the type of gamete produced in a gametangium, several types can be distinguished.

Female

Main article: Archegonium

Female gametangia are most commonly called archegonia. They produce egg cells and are the sites for fertilization. Archegonia are common in algae and primitive plants as well as gymnosperms. In flowering plants, they are replaced by the embryo sac inside the ovule. An archegonium (pl: archegonia) (from the Greek arche = beginning and gonos = born) is a multicellular structure or organ of the gametophyte phase of certain plants producing and containing the ovum or female gamete. ... An archegonium (pl: archegonia) (from the Greek arche = beginning and gonos = born) is a multicellular structure or organ of the gametophyte phase of certain plants producing and containing the ovum or female gamete. ... For the video-related acronym, see OVA. A human ovum An ovum (or loosely, egg or egg cell) is a female sex cell or gamete. ... Categories: Biology stubs ... Divisions Pinophyta - Conifers Ginkgophyta - Ginkgo Cycadophyta - Cycads Gnetophyta - Gnetum, Ephedra, Welwitschia Gymnosperms (Gymnospermae) are a group of seed-bearing plants with ovules on the edge or blade of an open sporophyll, the sporophylls usually arranged in cone-like structures. ... It has been suggested that Angiospermae, and Anthophyta be merged into this article or section. ... This article or section does not adequately cite its references or sources. ...

Male

Main article: Antheridium

The male gametangia are most commonly called antheridia. They produce sperm cells that they release for fertilization. Antheridia producing non-motile sperm (spermatia) are called spermatangia. Some antheridia do not release their sperm. 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. In "higher" plants such as conifers and flowering plants, they are replaced by pollen grains. Diagram of antheridium anatomy An antheridium (plural: antheridia) is a structure or organ of the gametophyte phase of certain plants producing and containing the spermatids or male gametes. ... Diagram of antheridium anatomy An antheridium (plural: antheridia) is a structure or organ of the gametophyte phase of certain plants producing and containing the spermatids or male gametes. ... Different types of sperm cells: A) spermatozoon (motile), B) spermatium (non-motile), C) fertilization tube with sperm nuclei For other uses, see Sperm (disambiguation). ... Orders Lagenidiales Leptomitales Peronosporales Pythiales Rhipidiales Saprolegniales Sclerosporales Water moulds or Oomycetes are a group of filamentous protists, physically resembling fungi. ... In biology, a syncytium is a large region of cytoplasm that contains many nuclei. ... The eukaryotic cell nucleus. ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... Bryophytes are embryophyte plants (land plants) that are nevertheless non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. ... Classes Psilotopsida Equisetopsida Marattiopsida Polypodiopsida A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta. ... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Leaves and male cone of Cycas revoluta Cycads are an ancient group of seed plants characterized by a large crown of compound leaves and a stout trunk. ... Binomial name Ginkgo biloba L. The Ginkgo (Ginkgo biloba), frequently misspelled as Gingko, and sometimes known as the Maidenhair Tree, is a unique tree with no close living relatives. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... It has been suggested that Angiospermae, and Anthophyta be merged into this article or section. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomea purpurea), hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ...

Isogamous

In isogamy, the gametes look alike and cannot be classified into "male" or "female." For example, in zygomycetes, two gametangia (single cells at the end of hyphae) form upon contact with each other and fuse into a zygote. A gamete is a specialized germ cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... Zygomycota, or zygote fungi, are a division of fungi. ... Hyphae as seen under a log A hypha (plural hyphae) is a long, branching filament found primarily in fungi, but also in fungus-like bacteria such as Actinomyces and Streptomyces. ... A zygote (Greek: ζυγωτόν) is a cell that is the result of fertilization. ...