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Carposporangia
A carpospore is a diploid spore produced by red algae. After fertilization, the alga's carpogonium The carpogonium (plural ''carpogonia'') is the female organ in the red algae (Rhodophyta) which have a highly specialized type of reproduction. It contains the reproductive nucleus. It may contain a number of cells usually without chloroplasts. I ... subdivides into carpospores, and generally the largest type of spore (larger than bispores, which are larger again than tetraspores). The wall of the carposporangium then breaks down, releasing the spores into the environment. References Red algae {{rhodophyta-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Algae
Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species within over 900 Genus, genera amidst ongoing taxonomic revisions. The majority of species (6,793) are Florideophyceae, and mostly consist of multicellular, ocean, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, no terrestrial species exist, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. Red algae form a distinct group characterized by eukaryotic cells without flagella and centrioles, chloroplasts without external endoplasmic reticulum or unstack ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more sets of chromosomes. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the Biological life cycle, life cycles of many plants, algae, fungus, fungi and protozoa. They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. In some rare cases, a diploid spore is also p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpogonium
The carpogonium (plural ''carpogonia'') is the female organ in the red algae (Rhodophyta) which have a highly specialized type of reproduction. It contains the reproductive nucleus. It may contain a number of cells usually without chloroplasts. It shows an elongated process which is the receptive organ for the male gametes. It gives birth to the carpospore A carpospore is a diploid spore produced by red algae Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized spe ...s. It may also have hairlike structures called '' trichogynes'' which receive sperm before fertilization takes place."trichogyne". Dictionary.com Unabridged. Random House, Inc. 14 September 2017. Dictionary.com http://www.dictionary.com/browse/trichogyne References Red algae {{rhodophyta-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraspores
Tetraspores are red algae spores produced by the tetrasporophytic (diploid) phase in the life history of algae in the Rhodophyta as a result of meiosis.Jones, W.E. Revised and reprinted 1964. A Key to the genera of the British seaweeds.''Field Studies''. Vol 1 (4) pp.1 – 32 The name is derived from the 4 spores that form after this meiosis, the division is of three kinds: cruciate, zonate and tetrahedral In geometry, a tetrahedron (: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular Face (geometry), faces, six straight Edge (geometry), edges, and four vertex (geometry), vertices. The tet .... References Red algae Reproduction {{rhodophyta-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
