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Maullinia Ectocarpii
''Maullinia'' is a genus of intracellular, phytomyxid parasites found across the Southern Hemisphere though primarily in Chile, The Prince Edward Islands, South Africa, Australia, and New Zealand. These parasites infiltrate the cells of their brown algal hosts via cytoplasmic extensions called plasmodia that divide synchronously, becoming increasingly multi-nucleate and engulfing the host cell organelles as they grow. Eventually, as the plasmodia fill the entire cell volume, the host cells become hypertrophied and grow to 3- 4x their original size, showing up as swollen appendages or galls on the host tissue at a macroscopic level. These swollen regions will burst alongside the mature ''Maullinia'' plasmodia, releasing biflagellated zoospores to the inter- and extracellular space to disperse the infection further. Zoospores can come from sporangial plasmodia, as in ''M. ectocarpii'', or from resting spores, as in ''M. braseltonii''. As ''Maullinia'' can infect a wide range com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durvillaea Antarctica
''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal erosion facilitated by bull-kelp ''Durvillaea antarctica'' at subantarctic Macquarie Island, ''Antarctic Science'' 10 (4), 431–438. . ''D. antarctica'', an alga, does not have air bladders, but floats due to a unique honeycomb structure within the alga's blades, which also helps the kelp avoid being damaged by the strong waves.Maggy WassilieffSeaweed - Bull kelp’s honeycombed structure ''Te Ara - the Encyclopedia of New Zealand'', Ministry of Culture and Heritage. Updated 2 March 2009. Retrieved 9 March 2010. Taxonomy The species was first described in 1822, as ''Fucus antarcticus'', and revised in 1892 as ''Durvillaea antarctica''. The genus name ''Durvillaea'' was given in memory of the French explorer Jules Dumont d'Urville, while the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epiphyte
An epiphyte is a plant or plant-like organism that grows on the surface of another plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phorophytes. Epiphytes take part in nutrient cycles and add to both the diversity and biomass of the ecosystem in which they occur, like any other organism. In some cases, a rainforest tree's epiphytes may total "several tonnes" (several long tons). They are an important source of food for many species. Typically, the older parts of a plant will have more epiphytes growing on them. Epiphytes differ from parasites in that they grow on other plants for physical support and do not necessarily affect the host negatively. An organism that grows on another organism that is not a plant may be called an epibiont. Epiphytes are usually found in the temperate zone (e.g., many mosses, liverworts, lichens, and algae) or in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporophyte
A sporophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the biological life cycle, life cycles of plants and algae. It is a diploid multicellular organism which produces asexual Spore, spores. This stage Alternation of generations, 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 Embryophyta, 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 Spermatophyte, seed plants, the largest groups of which are the gymnosperms (bare seeds) and angiosperms (fruiting plants), the sporophyte phase is more prominent than the gametophyte, and is the familiar green plant with its roots, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durvillaea
''Durvillaea'' is a genus of large brown algae in the monotypic family Durvillaeaceae. All members of the genus are found in the southern hemisphere, including Australia, New Zealand, South America, and various subantarctic islands. ''Durvillaea'', commonly known as southern bull kelps, occur on rocky, wave-exposed shorelines and provide a habitat for numerous intertidal organisms. Many species exhibit a honeycomb-like structure in their fronds that provides buoyancy, which allows individuals detached from substrates to raft alive at sea, permitting dispersal for hundreds of days over thousands of kilometres. ''Durvillaea'' species have been used for clothing, tools and as a food source by many indigenous cultures throughout the South Pacific, and they continue to play a prominent role in Chilean cuisine. Common name and etymology The common name for ''Durvillaea'' is southern bull kelp. This is often shortened to bull kelp, which can generate confusion with the North Pacific ke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporangium
A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many other groups form sporangia at some point in their biological life cycle, life cycle. Sporangia can produce spores by mitosis, but in land plants and many fungi, sporangia produce genetically distinct haploid spores by meiosis. It's outdated name, sporange, is one of the few perfect rhymes for Orange (colour), orange. Fungi In some phyla of fungi, the sporangium plays a role in asexual reproduction, and may play an indirect role in sexual reproduction. The sporangium forms on the sporangiophore and contains Ploidy, haploid Cell nucleus, nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via wind and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametophyte
A gametophyte () is one of the two alternating 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 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'', the gametes are isogamous, all of one size, shape and general morphology. Land plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filamentous Algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular microalgae, such as cyanobacteria, ''Chlorella'', and diatoms, to multicellular macroalgae such as kelp or brown algae which may grow up to in length. Most algae are aquatic organisms and lack many of the distinct cell and tissue types, such as stomata, xylem, and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds. In contrast, the most complex freshwater forms are the Charophyta, a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. Algae that are carried passively by water are plankton, specifically phytoplankton. Algae constitute a polyphyletic group because they do not include a common ancestor, and although eukaryotic algae with chlorophyll-bearing plastids seem to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macroscopic Scale
The macroscopic scale is the length scale on which objects or phenomena are large enough to be visible with the naked eye, without magnifying optical instruments. It is the opposite of microscopic. Overview When applied to physical phenomena and bodies, the macroscopic scale describes things as a person can directly perceive them, without the aid of magnifying devices. This is in contrast to observations ( microscopy) or theories ( microphysics, statistical physics) of objects of geometric lengths smaller than perhaps some hundreds of micrometres. A macroscopic view of a ball is just that: a ball. A microscopic view could reveal a thick round skin seemingly composed entirely of puckered cracks and fissures (as viewed through a microscope) or, further down in scale, a collection of molecules in a roughly spherical shape (as viewed through an electron microscope). An example of a physical theory that takes a deliberately macroscopic viewpoint is thermodynamics. An exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laminariales
Kelps are large brown algae or seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance and use of photosynthesis in chloroplasts, kelp is technically not a plant but a stramenopile (a group containing many protists). Kelp grow from stalks close together in very dense areas like forests under shallow temperate and Arctic oceans. They were previously thought to have appeared in the Miocene, 5 to 23 million years ago based on fossils from California. New fossils of kelp holdfasts from early Oligocene rocks in Washington State show that kelps were present in the northeastern Pacific Ocean by at least 32 million years ago. The organisms require nutrient-rich water with temperatures between . They are known for their high growth rate—the genera ''Macrocystis'' and ''Nereocystis'' can grow as fast as half a metre a day (that is, about 20 inches a day), ultimately reaching .Thomas, D. 2002. ''Seaweeds.'' The Natural History Museum, Lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fucales
The Fucales (fucoids) are an order in the brown algae (class Phaeophyceae). The list of families in the Fucales, as well as additional taxonomic information on algae, is publicly accessible at Algaebase. The class Phaeophyceae is included within the division Heterokontophyta.Hardy, G. and Guiry, M.D. 2006. ''A Check-list and Atlas of the Seaweeds of Britain and Ireland.'' 2006. The British Phycologcal Society. This name comes from the Greek word ''phaios'' meaning "brown" and ''phyton'' meaning plant.Huisman, J.M. 2000. ''Marine Plants of Australia''. University of Western Australia Press, Australia. They include some of the largest organisms in the sea, but some are small and fine in structure. Classification The Fucales include some of the more common littoral seaweeds and the members of the order have the typical seaweed construction: a holdfast, stipe, and lamina Lamina may refer to: People * Saa Emerson Lamina, Sierra Leonean politician * Tamba Lamina, Sierra Leo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectocarpales
Ectocarpales is a very large order (biology), order in the brown algae (class Phaeophyceae). The order includes families with pseudoparenchymatous (Splachnidiaceae) or true parenchymatous (Scytosiphonaceae) tissue. Pseudoparenchymatous refers to a filamentous alga with cells packed very close together to give an appearance of parenchymatous tissue, the latter being composed of cells which can truly divide in three dimensions, unusual among the algae. Filamentous algae are composed of cells that divide along a single plane, allowing only elongation to form filaments of one or more rows of cells. Algae that can divide in two planes can form sheet-like Thallus (tissue), thalli or bodies. Cells that can divide in a third plane potentially allow for the organism to develop a more complex body plan, and diversification of body plans into an erect thallus of some sort and a holdfast (biology), holdfast for attaching the upright portion to the substrate. A 2014 classification recogni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
