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Gazania Linearis
''Gazania'' is a genus of flowering plants in the family Asteraceae, native to Southern Africa.Per Ola Karis. 2007. "Arctotideae" pages 200-207. In: Klaus Kubitzki (series editor); Joachim W. Kadereit and Charles Jeffrey (volume editors). ''The Families and Genera of Vascular Plants'' volume VIII. Springer-Verlag: Berlin; Heidelberg, Germany. They produce large, daisy-like composite flowerheads in brilliant shades of yellow and orange, over a long period in summer. They are often planted as drought-tolerant groundcover. Taxonomic history The genus was first formally described by German botanist Joseph Gaertner in the second volume of his major work '' De Fructibus et Seminibus Plantarum'' in 1791. Gaertner named the genus after Theodorus Gaza, a 15th-century translator of the works of Theophrastus.Seranne Howis, Nigel P. Barker, and Ladislav Mucina. 2009. "Globally grown, but poorly known: species limits and biogeography of ''Gazania'' Gaertn. (Asteraceae) inferred from ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Gaertner
Joseph Gaertner (12 March 1732 – 14 July 1791) was a German botanist, best known for his work on seeds, ''De Fructibus et Seminibus Plantarum'' (1788-1792). Biography He was born in Calw, and studied in Göttingen under Albrecht von Haller. He was primarily a naturalist, but also worked at physics and zoology. He travelled extensively to visit other naturalists. He was professor of anatomy in Tübingen in 1760, and was appointed professor of botany at St Petersburg in 1768, but returned to Calw in 1770. Gaertner made back cross to convert one species into another. Back cross increases nuclear gene frequency His observations were: 1. Dominance of traits 2. Equal contribution of male and female to the progeny 3. No variation in F1 (first generation of descendants) 4. Large variation in F2 (second generation of descendants) including parental and intermediate types 5. Some of F2 plants had entirely new traits but he was unable to give possible explanation for observed dat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tribe (biology)
In biology, a tribe is a taxonomic rank above genus, but below family and subfamily. It is sometimes subdivided into subtribes. By convention, all taxa ranked above species are capitalized, including both tribe and subtribe. In zoology, the standard ending for the name of a zoological tribe is "-ini". Examples include the tribes Caprini (goat-antelopes), Hominini (hominins), Bombini (bumblebees), and Thunnini (tunas). The tribe Hominini is divided into subtribes by some scientists; subtribe Hominina then comprises "humans". The standard ending for the name of a zoological subtribe is "-ina". In botany, the standard ending for the name of a botanical tribe is "-eae". Examples include the tribes Acalypheae and Hyacintheae. The tribe Hyacintheae is divided into subtribes, including the subtribe Massoniinae. The standard ending for the name of a botanical subtribe is "-inae". In bacteriology, the form of tribe names is as in botany, e.g., Pseudomonadeae, based on the ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Sequence
A nucleic acid sequence is a succession of bases within the nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. This succession is denoted by a series of a set of five different letters that indicate the order of the nucleotides. By convention, sequences are usually presented from the 5' end to the 3' end. For DNA, with its double helix, there are two possible directions for the notated sequence; of these two, the sense strand is used. Because nucleic acids are normally linear (unbranched) polymers, specifying the sequence is equivalent to defining the covalent structure of the entire molecule. For this reason, the nucleic acid sequence is also termed the primary structure. The sequence represents genetic information. Biological deoxyribonucleic acid represents the information which directs the functions of an organism. Nucleic acids also have a secondary structure and tertiary structure. Primary structure is sometimes mistakenly referred to as "prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Nucleus
The cell nucleus (; : nuclei) is a membrane-bound organelle found in eukaryote, eukaryotic cell (biology), cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have #Anucleated_cells, no nuclei, and a few others including osteoclasts have Multinucleate, many. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm; and the nuclear matrix, a network within the nucleus that adds mechanical support. The cell nucleus contains nearly all of the cell's genome. Nuclear DNA is often organized into multiple chromosomes – long strands of DNA dotted with various proteins, such as histones, that protect and organize the DNA. The genes within these chromosomes are Nuclear organization, structured in such a way to promote cell function. The nucleus maintains the integrity of genes and controls the activities of the ... [...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] |
Molecular Phylogenetic
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to determine the processes by which diversity among species has been achieved. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree. Molecular phylogenetics is one aspect of molecular systematics, a broader term that also includes the use of molecular data in taxonomy and biogeography. Molecular phylogenetics and molecular evolution correlate. Molecular evolution is the process of selective changes (mutations) at a molecular level (genes, proteins, etc.) throughout various branches in the tree of life (evolution). Molecular phylogenetics makes inferences of the evolutionary relationships that arise due to molecular evolution and results in the construction of a phylogenetic tree. History The theoretical fra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogeny
A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA. In other words, it is a branching diagram or a tree (graph theory), tree showing the evolutionary relationships among various biological species or other entities based upon similarities and differences in their physical or genetic characteristics. In evolutionary biology, all life on Earth is theoretically part of a single phylogenetic tree, indicating common ancestry. Phylogenetics is the study of phylogenetic trees. The main challenge is to find a phylogenetic tree representing optimal evolutionary ancestry between a set of species or taxa. computational phylogenetics, Computational phylogenetics (also phylogeny inference) focuses on the algorithms involved in finding optimal phylogenetic tree in the phylogenetic landscape. Phylogene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academic Publishing
Academic publishing is the subfield of publishing which distributes Research, academic research and scholarship. Most academic work is published in academic journal articles, books or Thesis, theses. The part of academic written output that is not formally published but merely printed up or posted on the Internet is often called "grey literature". Most scientific and scholarly journals, and many academic and scholarly books, though not all, are based on some form of academic peer review, peer review or editorial refereeing to qualify texts for publication. Peer review quality and selectivity standards vary greatly from journal to journal, publisher to publisher, and field to field. Most established academic disciplines have their own journals and other outlets for publication, although many academic journals are somewhat interdisciplinarity, interdisciplinary, and publish work from several distinct fields or subfields. There is also a tendency for existing journals to divide into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helmut Roessler
Helmut is a German name. Variants include Hellmut, Helmuth, and Hellmuth. From old German, the first element deriving from either ''heil'' ("healthy") or ''hiltja'' ("battle"), and the second from ''muot'' ("spirit, mind, mood"). Helmut may refer to: People A–L *Helmut Angula (born 1945), Namibian politician * Helmut Ashley (1919–2021), Austrian director and cinematographer *Helmut Bakaitis (born 1944), Australian director and actor *Helmut Berger (1944–2023), Austrian actor *Helmut Dantine (1917–1982), Austrian actor * Helmut Deutsch (born 1945), Austrian classical pianist *Helmut Ditsch (born 1962), Argentine painter * Hellmut Diwald (1924–1993), German historian * Helmut Donner (born 1941), Austrian high jumper *Helmut Duckadam (1959–2024), Romanian footballer *Helmut Fischer (1926–1997), German actor * Hellmut von Gerlach (1866–1935), German journalist * Helmut Goebbels (1935–1945), only son of Joseph Goebbels * Helmut Graeb, German electrical engineer *Helmu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorteria
''Gorteria'' is a genus of small Annual plant, annual herbaceous plants or shrubs that is assigned to the Asteraceae, daisy family (Compositae or Asteraceae). It includes 12 species native to eastern and southern Africa, ranging from Ethiopia to South Africa. Like in almost all Asteraceae, the individual flowers are Merosity, 5-merous, small and clustered in typical heads, and are surrounded by an Bract#Involucral bracts, involucre, consisting of in this case several Whorl (botany), whorls of bracts, which are merged at their base. In ''Gorteria'', the centre of the head is taken by relatively few bisexual and sometimes also male, yellow to orange Asteraceae#Floral heads, disc florets, and is surrounded by one complete whorl of 5–14 infertile cream to dark orange Asteraceae#Floral heads, ray florets, sometimes with a few ray florets nearer to the centre. None, some or all of them may have darker spots at their base. The fruits remain attached to their common base when ripe, and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hirpicium
''Gorteria'' is a genus of small annual herbaceous plants or shrubs that is assigned to the daisy family (Compositae or Asteraceae). It includes 12 species native to eastern and southern Africa, ranging from Ethiopia to South Africa. Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and are surrounded by an involucre, consisting of in this case several whorls of bracts, which are merged at their base. In ''Gorteria'', the centre of the head is taken by relatively few bisexual and sometimes also male, yellow to orange disc florets, and is surrounded by one complete whorl of 5–14 infertile cream to dark orange ray florets, sometimes with a few ray florets nearer to the centre. None, some or all of them may have darker spots at their base. The fruits remain attached to their common base when ripe, and it is the entire head that breaks free from the plant. One or few seeds germinate inside the flower head which can be found a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
