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Conferva
''Cladophora'' is a genus of reticulated filamentous Ulvophyceae ( green algae). The genus ''Cladophora'' contains many species that are very hard to tell apart and classify, mainly because of the great variation in their appearances, which is affected by habitat, age and environmental conditions. Unlike ''Spirogyra'' the filaments of ''Cladophora'' branch and do not undergo conjugation. There are two multicellular stages in its life cycle – a haploid gametophyte and a diploid sporophyte – which look highly similar. The only way to tell the two stages apart is to either count their chromosomes, or examine their offspring. The haploid gametophyte produces haploid gametes by mitosis and the diploid sporophyte produces haploid spores by meiosis. The only visible difference between the gametes and spores of ''Cladophora'' is that the gametes have two flagella and the spores have four. The ''Cladophora'' species can be a major nuisance causing major alteration to benthic co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladophora Vagabunda
''Cladophora vagabunda'' is a species of marine green algae in the family Cladophoraceae Cladophoraceae are a family of green algae in the order the Cladophorales.See the NCBIbr>webpage on Cladophoraceae Data extracted from the This family includes notably the genus ''Chaetomorpha ''Chaetomorpha'' is a genus of green algae in t .... It has a worldwide distribution. References External links * ''Cladophora vagabunda'' at AlgaeBase''Cladophora vagabunda'' at global name index''Cladophora vagabunda'' at the World Register of Marine Species (WoRMS) Plants described in 1963 Cladophoraceae {{Ulvophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Traugott Kützing
Friedrich Traugott Kützing (8 December 1807 in Kalbsrieth, Ritteburg – 9 September 1893) was a German pharmacist, botanist and phycologist. Despite his limited background in regard to higher education, Kützing made significant scientific contributions. In 1833, he demonstrated differences between diatoms and desmids, thus separating the two groups into families of their own. Also, independent of Charles Cagniard-Latour (1777–1859) and Theodor Schwann (1810–1882), he was among the first to provide comprehensive answers in regard to yeast and the role it played in fermentation. In 1849, he published ''Species Algarum'', a massive work that provided descriptions for 6000 species of algae. He is the binomial authority, taxonomic authority of the genera ''Syringodium'' (family Cymodoceaceae) and ''Phlebothamnion'' (family Ceramiaceae). Early life As a young man, he worked in several pharmacies in Germany, also serving as assistant for a few semesters at the chemical-pharma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladophora Scopaeformis
''Cladophora'' is a genus of reticulated filamentous Ulvophyceae (green algae). The genus ''Cladophora'' contains many species that are very hard to tell apart and classify, mainly because of the great variation in their appearances, which is affected by habitat, age and environmental conditions. Unlike ''Spirogyra'' the filaments of ''Cladophora'' branch and do not undergo conjugation. There are two multicellular stages in its life cycle – a haploid gametophyte and a diploid sporophyte – which look highly similar. The only way to tell the two stages apart is to either count their chromosomes, or examine their offspring. The haploid gametophyte produces haploid gametes by mitosis and the diploid sporophyte produces haploid spores by meiosis. The only visible difference between the gametes and spores of ''Cladophora'' is that the gametes have two flagella and the spores have four. The ''Cladophora'' species can be a major nuisance causing major alteration to benthic condition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitosis
In cell biology, mitosis () is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is maintained. Therefore, mitosis is also known as equational division. In general, mitosis is preceded by S phase of interphase (during which DNA replication occurs) and is often followed by telophase and cytokinesis; which divides the cytoplasm, organelles and cell membrane of one cell into two new cells containing roughly equal shares of these cellular components. The different stages of mitosis altogether define the mitotic (M) phase of an animal cell cycle—the division of the mother cell into two daughter cells genetically identical to each other. The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. These stages are preprophase (specific to plant cells), prophase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporophyte
A sporophyte () is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote produced when a haploid egg cell is fertilized by a haploid sperm and each sporophyte cell therefore has a double set of chromosomes, one set from each parent. All land plants, and most multicellular algae, have life cycles in which a multicellular diploid sporophyte phase alternates with a multicellular haploid gametophyte phase. In the seed plants, the largest groups of which are the gymnosperms and flowering plants (angiosperms), the sporophyte phase is more prominent than the gametophyte, and is the familiar green plant with its roots, stem, leaves and cones or flowers. In flowering plants the gametophytes are very reduced in size, and are represented by the germinated pollen and the embryo sac. The sporophyte produces spores (hence t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametophyte
A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has one set of chromosomes. The gametophyte is the Sexual reproduction of plants, sexual phase in the life cycle of plants and algae. It develops sex organs that produce gametes, haploid sex cells that participate in fertilization to form a diploid zygote which has a double set of chromosomes. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte. The sporophyte can produce haploid spores by meiosis that on germination produce a new generation of gametophytes. Algae In some multicellular green algae (''Ulva lactuca'' is one example), red algae and brown algae, sporophytes and gametophytes may be externally indistinguishable (isomorphic). In ''Ulva (genus), Ulv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ploidy
Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, Tissue (biology), tissues, and Individual#Biology, 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 polyploidy, polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexual reproduction, sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirogyra
''Spirogyra'' (common names include water silk, mermaid's tresses, and blanket weed) is a genus of filamentous charophyte green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is characteristic of the genus. ''Spirogyra'' species, of which there are more than 400, are commonly found in freshwater habitats. ''Spirogyra'' measures approximately 10 to 100 μm in width and may grow to several centimetres in length. It is often observed as green slimy patches on the ground near ponds and other water bodies having stagnant water. General characteristics ''Spirogyra'' is very common in relatively clear eutrophic water, developing slimy filamentous green masses. In spring ''Spirogyra'' grows under water, but when there is enough sunlight and warmth they produce large amounts of oxygen, adhering as bubbles between the tangled filaments. The filamentous masses come to the surface and become visible as slimy green mats. ''Spirogyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Algae
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as sister of the Zygnematophyceae. Since the realization that the Embryophytes emerged within the green algae, some authors are starting to properly include them. The completed clade that includes both green algae and embryophytes is monophyletic and is referred to as the clade Viridiplantae and as the kingdom Plantae. The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. There are about 22,000 species of green algae. Many species live most of their lives as single cells, while other species form coenobia (colonies), long filaments, or highly differentiated macroscopic seaweeds. A few other organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulvophyceae
The Ulvophyceae or ulvophytes are a class of green algae, distinguished mainly on the basis of ultrastructural morphology, life cycle and molecular phylogenetic data.Graham LE, Graham JM, Wilcox LW (2009) ''Algae''. 2nd Edition. Benjamin Cummings (Pearson), San Francisco, CA The sea lettuce, ''Ulva'', belongs here. Other well-known members include ''Caulerpa'', ''Codium'', ''Acetabularia'', ''Cladophora'', '' Trentepohlia'' and ''Monostroma''. The Ulvophytes are diverse in their morphology and their habitat. Most are seaweeds such as those listed above. Others, such as ''Rhizoclonium'', ''Pithophora'' and some species of ''Cladophora'' live in fresh water and in some areas are considered weeds. Evolution The origin and early diversification of the Ulvophyceae likely took place in the late Neoproterozoic. Although most contemporary ulvophytes are marine macroalgae (seaweeds), ancestral ulvophytes may have been freshwater, unicellular green algae. Molecular phylogenetic eviden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypha
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria, and sometimes nuclei to flow between cells. The major structural polymer in fungal cell walls is typically chitin, in contrast to plants and oomycetes that have cellulosic cell walls. Some fungi have aseptate hyphae, meaning their hyphae are not partitioned by septa. Hyphae have an average diameter of 4–6 µm. Growth Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and polymerization of cell wall components, and the internal production of new cell membrane. The S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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