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Asplenium Tenerrimum
''Asplenium'' is a genus of about 700 species of ferns, often treated as the only genus in the family (biology), family Aspleniaceae, though other authors consider ''Hymenasplenium'' separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is ''Asplenium marinum''. The most common vernacular name is spleenworts, applied to the more "typical" species. ''Asplenium nidus, A. nidus'' and several similar species are called bird's-nest ferns, the ''Camptosorus'' group is known as walking ferns, and distinct names are applied to some other particularly well-known species. Etymology From Neo-Latin, New Latin ''asplenium'' (“spleenworts”), Carolus Linnaeus, Linnaeus's adjustment of Latin ''asplenon'' (“spleenwort”), from Ancient Greek ἄσπληνον (''ásplēnon'', “spleenwort”), from ἀ- (''a-'', “un-”) + σπλήν (''splḗn'', “spleen”) + -ο� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium Trichomanes
''Asplenium trichomanes'', the maidenhair spleenwort (not to be confused with the similar-looking Adiantum, maidenhair fern), is a small fern in the spleenwort genus ''Asplenium''. It is a widespread and common species, occurring almost worldwide in a variety of rocky habitats. It is a variable fern with several subspecies. The binomial nomenclature, specific epithet ''trichomanes'' refers to a Greek word for fern. Description ''Asplenium trichomanes'' is a small plant forming tufts between tall, arising from a short, scaly rhizome. The scales are dark and the evergreen fronds are long and narrow, gradually tapering towards the tip. They are simply divided into small, yellow-green to dark-green, roundish leaflets or pinnae. The stipe (botany), stipe and rachis of the frond are dark all along their length. The fronds can reach in length but are more commonly between . The Sorus, indusia are linear to oval, straight, and attached to the upper-side of the fertile vein. There are u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carolus Linnaeus
Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern Taxonomy (biology), taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was the son of a curate and was born in Råshult, in the countryside of Småland, southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistic
Cladistics ( ; from Ancient Greek 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies) that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a ' grade', which are fruitless to precisely delineate, especially when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introduction To Evolution
In biology, evolution is the process of change in all forms of life over generations, and evolutionary biology is the study of how evolution occurs. Biological populations evolve through genetics, genetic changes that correspond to changes in the organisms' phenotypic trait, observable traits. Genetic changes include mutations, which are caused by damage or replication errors in organisms' DNA. As the genetic variation of a population genetic drift, drifts randomly over generations, natural selection gradually leads traits to become more or less common based on the relative reproductive success of organisms with those traits. The age of the Earth is about 4.5 billion years. The earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago. Evolution does not attempt to explain the origin of life (covered instead by abiogenesis), but it does explain how early lifeforms evolved into the complex ecosystem that we see today. Based on the similarities betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastome
Chloroplast DNA (cpDNA), also known as plastid DNA (ptDNA) is the DNA located in chloroplasts, which are photosynthetic organelles located within the cells of some eukaryotic organisms. Chloroplasts, like other types of plastid, contain a genome separate from that in the cell nucleus. The existence of chloroplast DNA was identified biochemically in 1959, and confirmed by electron microscopy in 1962. The discoveries that the chloroplast contains ribosomes and performs protein synthesis revealed that the chloroplast is genetically semi-autonomous. The first complete chloroplast genome sequences were published in 1986, '' Nicotiana tabacum'' (tobacco) by Sugiura and colleagues and '' Marchantia polymorpha'' (liverwort) by Ozeki et al. Since then, tens of thousands of chloroplast genomes from various species have been sequenced. Molecular structure Chloroplast DNAs are circular, and are typically 120,000–170,000 base pairs long. They can have a contour length of around 30– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle, organelle known as a plastid that conducts photosynthesis mostly in plant cell, plant and algae, algal cells. Chloroplasts have a high concentration of chlorophyll pigments which capture the Radiant energy, energy from sunlight and convert it to chemical energy and release oxygen. The chemical energy created is then used to make sugar and other organic molecules from carbon dioxide in a process called the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in some unicellular algae, up to 100 in plants like ''Arabidopsis'' and wheat. Chloroplasts are highly dynamic—they circulate and are moved around within cells. Their behavior is strongly influenced by environmental factors like light color and intensity. Chloroplasts cannot be made anew by the plant cell and must ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypodiales
The Order (biology), order Polypodiales encompasses the major lineages of polypod ferns, which comprise more than 80% of today's fern species. They are found in many parts of the world including Tropics, tropical, semitropical and Temperate climate, temperate areas. Description Polypodiales are unique in bearing sporangia with a vertical Annulus (botany), annulus interrupted by the stalk and stomium. These sporangial characters were used by Johann Jakob Bernhardi to define a group of ferns he called the "Cathetogyratae"; the Pteridophyte Phylogeny Group has suggested reviving this name as the informal term cathetogyrates, to replace the ambiguously circumscribed term "polypods" when referring to the Polypodiales. The sporangia are born on stalks 1–3 cells thick and are often long-stalked. (In contrast, the Hymenophyllales have a stalk composed of four rows of cells.) The sporangia do not reach maturity simultaneously. Many groups in the order lack Sorus, indusia, but when presen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomic Rank
In biology, taxonomic rank (which some authors prefer to call nomenclatural rank because ranking is part of nomenclature rather than taxonomy proper, according to some definitions of these terms) is the relative or absolute level of a group of organisms (a ''taxon'') in a hierarchy that reflects evolutionary relationships. Thus, the most inclusive clades (such as Eukarya and Animalia) have the highest ranks, whereas the least inclusive ones (such as ''Homo sapiens'' or ''Bufo bufo'') have the lowest ranks. Ranks can be either relative and be denoted by an indented taxonomy in which the level of indentation reflects the rank, or absolute, in which various terms, such as species, genus, Family (biology), family, Order (biology), order, Class (biology), class, Phylum (biology), phylum, Kingdom (biology), kingdom, and Domain (biology), domain designate rank. This page emphasizes absolute ranks and the rank-based codes (the International Code of Zoological Nomenclature, Zoological Code, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systematic Botany
''Systematic Botany'' is a peer-reviewed scientific journal covering the study of systematic botany. It is published quarterly by the American Society of Plant Taxonomists. According to the ''Journal Citation Reports'', the journal has a 2010 impact factor of 1.897. ''Systematic Botany'' was established in spring 1976 under founding editor-in-chief William Louis Culberson (Duke University). The current editor-in-chief is James F. Smith (Boise State University). The American Society of Plant Taxonomists also publishes the peer-reviewed taxonomic monograph series, ''Systematic Botany Monographs'' since 1980. Abstracting and indexing ''Systematic Botany'' is abstracted and indexed in Agricola, Agris, BioOne, PubMed, Scirus, and Science Citation Index Expanded The Science Citation Index Expanded (SCIE) is a citation index owned by Clarivate and previously by Thomson Reuters. It was created by the Eugene Garfield at the Institute for Scientific Information, launched in 196 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance (a now discredited theory in modern genetics by particulate inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridization, which include genetic and morph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
