Red algae, or Rhodophyta (/ r o? ? d ? f ? t ? / roh-DOF-it-?, / ? r o? d ? ? f a? t ? / ROH-d?-FY-t?; from Ancient Greek ????? (rhodon) 'rose', and ????? (phyton) 'plant'), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7, currently recognized species with taxonomic revisions ongoing. Biological classification is how biologists group organisms.. The classification has its root in the work of Aristotle who invented a multi-ranked system. A great influence was Carolus Linnaeus, who popularized the idea of binomial nomenclature using a two-part name indicating the genus, and the mybajaguide.com human species is named Homo mybajaguide.com of species are often printed in italics.
The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioleschloroplasts that lack external endoplasmic reticulum and contain unstacked stroma thylakoidsand use phycobiliproteins as accessory pigmentswhich give them their red color. Most red algae are also multicellularmacroscopic, marine, and reproduce sexually. The red algal life history is typically an alternation of generations that may have three generations rather than two. Chloroplasts evolved following an endosymbiotic event between an ancestral, photosynthetic cyanobacterium and an early eukaryotic phagotroph.
The SCRP clade are microalgae, consisting of both unicellular forms and multicellular microscopic filaments and blades. The BF are macroalgae, seaweed that usually do not grow to more than about 50 cm in length, but a few species can reach lengths of 2 m.
While this was formerly attributed to the presence of pigments such as phycoerythrin that would permit red algae to inhabit greater depths than other macroalgae by chromatic adaption, recent evidence calls this into question e.
In the system of Adl et al. The authors use a hierarchical arrangement where how to regrind a cam clade names do not signify rank; the class name Rhodophyceae is used for the red algae. No subdivisions are given; the authors say, "Traditional subgroups are artificial constructs, and no longer valid. Many studies published since Adl et al. Below are other published taxonomies of the red algae using molecular and traditional alpha taxonomic data; however, the taxonomy of the red algae is still in a state of flux with classification above the level of order having received little scientific attention for most of the 20th century.
Some sources such as Lee place all red algae into the class "Rhodophyceae". Lee's organization is not a comprehensive classification, but a selection of orders considered common or important. A subphylum - Proteorhodophytina - has been proposed to encompass the existing classes CompsopogonophyceaePorphyridiophyceaeRhodellophyceae and Stylonematophyceae. Over 7, species are currently described for the red algae,  but the taxonomy is in constant flux with new species described each year.
Red algal morphology is diverse ranging from unicellular forms to complex parenchymatous and non- parenchymatous thallus. Red algae do not have flagella and centrioles during their entire life cycle. Presence of normal spindle fibres, microtubules, un-stacked photosynthetic membranes, presence of phycobilin pigment granules,  presence of pit connection between cells filamentous genera, absence of chloroplast endoplasmic reticulum are the distinguishing characters of red algal cell structure.
Presence of the water-soluble pigments called phycobilins phycocyanobilinphycoerythrobilinphycourobilin and phycobiliviolinwhich are localized into phycobilisomesgives red algae their distinctive color. Double membrane of chloroplast envelope surrounds the chloroplast. Absence of grana and attachment of phycobilisomes on the stromal surface of the thylakoid membrane are other distinguishing characters of red algal chloroplast.
Pit connections and pit plugs are unique and distinctive features of red algae that form during the process of cytokinesis following mitosis. Typically, a small pore is left in the middle of the newly formed partition.
The pit connection is formed where the daughter cells remain in contact. Shortly after the pit connection is formed, cytoplasmic continuity is blocked by the generation of a pit plug, which is deposited in the wall gap that connects the cells. Connections between cells having a common parent cell are called primary pit connections. Because apical growth is the norm in red algae, most cells have two primary pit connections, one to each adjacent cell.
Connections that exist between cells not sharing a common parent cell are labelled secondary pit connections. These connections are formed when an unequal cell division produced a nucleated daughter cell that then fuses to an adjacent cell. Patterns of secondary pit connections can be seen in the order Ceramiales. After a pit connection is formed, tubular membranes appear. A granular protein called the plug core then forms around the membranes.
The tubular membranes eventually disappear. While some orders of red algae simply have a plug core, others have an associated membrane at each side of the protein mass, called cap membranes. The pit plug continues to exist between the cells until one of the cells dies. When this happens, the living cell produces a layer of wall material that seals off the plug.
The pit connections have been suggested to function as structural reinforcement, or as avenues for cell-to-cell communication and transport in red algae, however little data supports this hypothesis. The reproductive cycle of red algae may what do you do with old pots and pans triggered by factors such as day length.
Asexual reproduction can occur through the production of spores and by vegetative means fragmentation, cell division or propagules production. Red algae lack motile sperm. Hence, they rely on water currents to transport their what are the similarities between algae and fungi to the female organs — although their sperm are capable of "gliding" to a carpogonium 's trichogyne.
The trichogyne will continue to grow until it encounters a spermatium ; once it has been fertilized, the cell wall at its base progressively thickens, separating it from the rest of the carpogonium at its base. Upon their collision, the walls of the spermatium and carpogonium dissolve.
The male nucleus divides and moves into the carpogonium; one half of the nucleus merges with the carpogonium's nucleus. The polyamine spermine is produced, which triggers carpospore production. Spermatangia may have long, delicate appendages, which increase their chances of "hooking up".
They display alternation of generations. In addition to a gametophyte generation, many have two sporophyte generations, the carposporophyte -producing carposporeswhich germinate into a tetrasporophyte — this produces spore tetrads, which dissociate and germinate into gametophytes. Carpospores may also germinate directly into thalloid gametophytes, or the carposporophytes may produce a tetraspore without going through a free-living tetrasporophyte phase.
The carposporophyte may be enclosed within the gametophyte, which may cover it with branches to form a cystocarp. In a simple case, such as Rhodochorton investiens :. In the Carposporophyte: a spermatium merges with a trichogyne a long hair on the female sexual organwhich then divides to form carposporangia — which produce carpospores.
Carpospores germinate into gametophytes, which produce sporophytes. Both of these are very similar; they produce monospores from monosporangia "just below a cross-wall in a filament"  and their spores are "liberated through the apex of sporangial cell.
The spores of a sporophyte produce either tetrasporophytes. Monospores produced by this phase germinates immediately, with no resting phase, to form an identical copy of the parent. Tetrasporophytes may also produce a carpospore, which germinates to form another tetrasporophyte. The gametophyte may replicate using monospores, but produces sperm in spermatangia, and "eggs"? A rather different example how to grow mushrooms at home youtube Porphyra gardneri :.
In its diploid phase, a carpospore can germinate to form a filamentous "conchocelis stage", which can also self-replicate using monospores. The conchocelis stage eventually produces conchosporangia. The resulting conchospore germinates to form a tiny prothallus with rhizoidswhich develops to a cm-scale leafy thallus.
This too can reproduce via monospores, which are produced inside the thallus itself. The latter group uses the more 13 C-negative CO 2 dissolved in sea water, whereas those with access to atmospheric carbon reflect the more positive signature of this reserve.
Photosynthetic pigments of Rhodophyta are chlorophylls a and d. Red algae are red due to phycoerythrin. They contain the sulfated polysaccharide carrageenan in the amorphous sections of their cell walls, although red algae from the genus Porphyra contain porphyran. They also produce a specific type of tannin called phlorotanninsbut in a lower amount than brown algae do. As enlisted in realDB 27 complete transcriptomes and 10 complete genomes sequences of red algae are available.
Listed below are the 10 what are some cultural issues in australia today genomes of red algae. One of the oldest fossils identified as a red alga is also the oldest fossil eukaryote that belongs to a specific modern taxon.
Bangiomorpha pubescensa multicellular fossil from arctic Canadastrongly resembles the modern red alga Bangia and occurs in rocks dating to 1. Two kinds of fossils resembling red algae were found sometime between and how to make homemade spaghetti sauce and meatballs well-preserved sedimentary rocks in Chitrakoot, central India.
The presumed red algae lie embedded in fossil mats of cyanobacteria, called stromatolites, what is the most important vitamin for your body 1. Red algae are important builders of limestone reefs. The earliest such coralline algae, the solenoporesare known from the Cambrian period. Other algae of different origins filled a similar role in the late Paleozoicand in more recent reefs.
Calcite crusts that have been interpreted as the remains of coralline red algae, date to the Ediacaran Period. Chromista and Alveolata algae e. According to this theory, over time these endosymbiont red algae have evolved to become chloroplasts. This part of endosymbiotic theory is supported by various structural and genetic similarities.
Red algae what are the similarities between algae and fungi a long history of use as a source of nutritional, functional food ingredients and pharmaceutical substances. Laver and Dulse Palmaria palmata  are consumed in Britain. These rhodophytes are easily grown and, for example, nori cultivation in Japan goes back more than three centuries. Cyanidium sp. Porphyra sp. Chondrus crispus Florideophyceae : Gigartinales.
Gracilaria sp. Florideophyceae: Gracilariales. Corallina officinalis sp. Florideophyceae: Corallinales. Laurencia sp. Florideophyceae: Ceramiales. Some red algae are iridescent when not covered with water. From Wikipedia, the free encyclopedia. Redirected from Rhodophyta. Division of archaeplastids. Temporal range: Mesoproterozoic—present .
Biological classification is how biologists group organisms. The classification has its root in the work of Aristotle who invented a multi-ranked system. A great influence was Carolus Linnaeus , who popularized the idea of binomial nomenclature using a two-part name indicating the genus , and the species. The human species is named Homo sapiens. Names of species are often printed in italics, although there is no obligation to do so this also goes for names of genera, etc. Biological classification is also known as taxonomy.
It is a science, and like most sciences has evolved over time. At various times different principles were adopted, and it is not rare for different scientists to use different methods.
Since the early 20th century, groupings are supposed to fit the Darwinian principle of common descent. These days, molecular evolution studies, which use DNA sequence analysis as data, are popular.
This is often called "phylogenetics", a branch or form of cladism. This approach creates an evolutionary Tree of life biology and uses characters traits to decide on the branches of the taxonomy. Sometimes organisms placed in the same group taxon are similar; such similarity is not necessarity coincidence.
It may be the result of shared descent from a common ancestor. Homologous traits are similarities caused by common ancestry. They are distinct from traits that are analogous. For example, birds and bats both have the power of flight, but this is not used to classify them together, because it is not inherited from a common ancestor.
In spite of all the other differences between them, the fact that bats and whales both feed their young on milk is one of the features used to classify both as mammals , since it was inherited from a common ancestor. When the present system of naming living things was developed, Latin was the language most widely used around the world. So, such names are still in Latin. The official descriptions and diagnoses of new taxa in Latin were and are written in Latin as well.
Zoologist allow any language for the description of animals. From January 1, , new taxa of algae, fungi and plants may be described in either English or Latin. Taxa above the genus level are often given names based on a "type genus ", with a standard suffix.
The suffixes used in forming these names depend on the kingdom, and sometimes the phylum and class, as set out in the table below. From Simple English Wikipedia, the free encyclopedia.
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