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Thoreales
Thoreales is an order of red algae belonging to the class Florideophyceae. The order consists only one family, Thoreaceae .Hassall, A.H. 1845. A history of the British freshwater algae, including descriptions of the Desmideae and Diatomaceae. With upwards of one hundred plates, illustrating the various species. Vol. I. pp. €“viii, €“462, , err. London, Edinburgh, Paris & Leipzig: S. Highley, H. Baillière; Sunderland & Knox; J.B. Baillière; T.O. Weigel. The family of ''Thoreaceae'' was circumscribed by Arthur Hill Hassall in A history of the British freshwater algae, including descriptions of the ''Desmideae'' and ''Diatomaceae'' in 1845. The family was originally placed in the Nemaliales order before being transferred to the newly created ''Batrachospermales'' order, before being placed later in ''Thoreales'' order in 2002. After various species of the family were analysed for the sequences of the genes coding for the large subunit of RUBISCO (rbcL) and the small subunit of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Algae
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, 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. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts that l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Florideophyceae
Florideophyceae is a class of red algae. They were once thought to be the only algae to bear pit connections, but these have since been found in the filamentous stage of the Bangiaceae. They were also thought only to exhibit apical growth, but there are genera known to grow by intercalary growth. Most, but not all, genera have three phases to the life cycle. Classification There are various classification schemes; see red algae. One option is to use the following: Subclass Hildenbrandiophycidae * Hildenbrandiales Subclass Nemaliophycidae * Acrochaetiales * Balbianiales * Balliales * Batrachospermales * Colaconematales * Nemaliales * Palmariales * Entwisleiales * Thoreales Subclass Corallinophycidae * Corallinales * Corallinapetrales * Rhodogorgonales * Sporolithales The subclass Corallinophycidae was introduced in 2007. Subclass Ahnfeltiophycidae * Ahnfeltiales * Pihiellales Subclass Rhodymeniophycidae * Bonnemaisoniales * Ceramiales * Gelidiales * G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorea
''Thorea'' is a genus of freshwater algae in the Phylum Rhodophyta (red algae). ''Thorea'' is a small alga with filaments up to 200 cm long, dark green in colour and not red as are marine Rhodophyta. The filaments have only as few secondary branches. ''Thorea'' is distributed throughout temperate and tropical regions. The genus was circumscribed by Jean Baptiste Bory de Saint-Vincent in Ann. Mus. Natl. Hist. Nat. vol.12 on page 126 in 1808. The genus name of ''Thorea'' is in honour of Jean Thore (1762–1823), who was a French botanist and physician who practiced medicine in the town of Dax. Species As accepted by WoRMS; *'' Thorea bachmannii'' *'' Thorea brodensis'' *'' Thorea clavata'' *'' Thorea conturba'' *'' Thorea flagelliformis'' *'' Thorea gaudichaudii'' *'' Thorea hispida'' *'' Thorea okadae'' *'' Thorea okaidai'' *'' Thorea prowsei'' *'' Thorea riekei'' *'' Thorea siamensis'' *'' Thorea violacea'' *'' Thorea zollingeri'' Former species; *''Thor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumscription (taxonomy)
In biological taxonomy, circumscription is the content of a taxon, that is, the delimitation of which subordinate taxa are parts of that taxon. If we determine that species X, Y, and Z belong in Genus A, and species T, U, V, and W belong in Genus B, those are our circumscriptions of those two genera. Another systematist might determine that T, U, V, W, X, Y, and Z all belong in genus A. Agreement on circumscriptions is not governed by the Codes of Zoological or Botanical Nomenclature, and must be reached by scientific consensus. A goal of biological taxonomy is to achieve a stable circumscription for every taxon. This goal conflicts, at times, with the goal of achieving a natural classification that reflects the evolutionary history of divergence of groups of organisms. Balancing these two goals is a work in progress, and the circumscriptions of many taxa that had been regarded as stable for decades are in upheaval in the light of rapid developments in molecular phylogenetics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Hill Hassall
Arthur Hill Hassall (13 December 1817, Teddington – 9 April 1894, San Remo) was a British physician, chemist and microscopist who is primarily known for his work in public health and food safety. Biography Hassall was born in Middlesex as the youngest son of five children in a house of a surgeon. His father was Thomas Hassall (1771–1844) and his mother, née Ann Sherrock ( 1778–1817). He spent his school years in Richmond. He entered medicine through apprenticeship in 1834 to his uncle Sir James Murray (1788–1871), spending his early career in Dublin, where he also studied botany and the seashore. In 1846 he published a two-volume study, ''The Microscopic Anatomy of the Human Body in Health and Disease'', the first English textbook on the subject. After further studying botany at Kew and publishing on botanical topics, particularly freshwater algae, he came to public attention with his 1850 book ''A microscopical examination of the water supplied to the inhabitants of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemaliales
Nemaliales is an order of red algae. It holds approximately 286 species. Families As accepted by AlgaeBase (with amount of species per genus); * Suborder Galaxaurineae (117) ** Galaxauraceae - 58 spp. **Scinaiaceae - 59 spp. * Suborder Nemaliineae (14) ** Liagoropsidaceae - 2 spp. ** Nemaliaceae - 9 spp. ** Yamadaellaceae 3 spp. Unplaced; *Liagoraceae Liagoraceae is a family of red algae (Rhodophyta) in the order Nemaliales. The type genus is ''Liagora'' . It was originally called ''Helminthocladiaceae'' by J.Agardh in 1851, but P. Silva in 1980 stated that this was predated by Liagoraceae w ... - 152 spp. References Red algae orders {{Rhodophyta-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RbcL
Ribulose-1,5-bisphosphate carboxylase-oxygenase, commonly known by the abbreviations RuBisCo, rubisco, RuBPCase, or RuBPco, is an enzyme () involved in the first major step of carbon fixation, a process by which atmospheric carbon dioxide is converted by plants and other photosynthetic organisms to energy-rich molecules such as glucose. In chemical terms, it catalyzes the carboxylation of ribulose-1,5-bisphosphate (also known as RuBP). It is probably the most abundant enzyme on Earth. Alternative carbon fixation pathways RuBisCO is important biologically because it catalyzes the primary chemical reaction by which inorganic carbon enters the biosphere. While many autotrophic bacteria and archaea fix carbon via the reductive acetyl CoA pathway, the 3-hydroxypropionate cycle, or the reverse Krebs cycle, these pathways are relatively small contributors to global carbon fixation compared to that catalyzed by RuBisCO. Phosphoenolpyruvate carboxylase, unlike RuBisCO, only temporarily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RRNA
Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal DNA (rDNA) and then bound to ribosomal proteins to form small and large ribosome subunits. rRNA is the physical and mechanical factor of the ribosome that forces transfer RNA (tRNA) and messenger RNA (mRNA) to process and translate the latter into proteins. Ribosomal RNA is the predominant form of RNA found in most cells; it makes up about 80% of cellular RNA despite never being translated into proteins itself. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins by mass. Structure Although the primary structure of rRNA sequences can vary across organisms, base-pairing within these sequences commonly forms stem-loop configurations. The length and position of these rRNA stem-loops allow them to create three-di ... [...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] |
Pit Connection
In algal anatomy, a pit connection is a hole in the septum between two algal cells, and is found only in the red algae − specifically, all orders except the Porphyridiales and haploid Bangiales. They are often stoppered with proteinaceous "pit plugs". By contrast, many fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ... (only ascomycetes and basidiomycetes, as most other groups lack septa) contain septal pores − an unrelated phenomenon. Characteristics A sieve-like membrane may cover the pit in living algae, but in the majority of algae a plug forms, they likely limit the transfer of metabolites between neighbouring cells. Formation Primary pit connections are formed between cells in the same filament, derived from the same parent cell by its division. Such connections ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
