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Rhizanthella
''Rhizanthella'', commonly known as underground orchids, is a genus of flowering plants in the orchid family, Orchidaceae and is endemic to Australia. All are leafless, living underground in symbiosis with mycorrhizal fungi. The inflorescence is a head of flowers held at, or just above the ground but mostly covered by soil or leaf litter and little is known about the mechanism of pollination. Description Orchids in the genus ''Rhizanthella'' are mostly underground, perennial, sympodial, mycotrophic herbs with fleshy underground stems which produce new shoots at nodes where there are colourless leaf-like cataphylls. There are no roots and new tubers form at the end of short stems. The leaves are reduced to scale-like structures lacking chlorophyll, pressed against and sheathing the stems. The inflorescence is a head containing many flowers and is held at, or just above ground level but the head is usually covered with leaf litter or soil. The head is surrounded by a large number o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizanthella Gardneri
''Rhizanthella gardneri'', commonly known as western underground orchid, is a species of flowering plant in the orchid family and is endemic to the southwest of Western Australia. It is a herb that spends its entire life cycle, including flowering, at or below the soil surface. A head of up to 100 small reddish to cream-coloured, inward facing flowers surrounded by large, cream-coloured bracts with a horizontal rhizome is produced between May and July. Description ''Rhizanthella gardneri'' is a leafless, sympodial herb with a horizontal rhizome below the soil surface. Beginning in late May to early June, the plant produces up to 100 small, inward-facing pinkish to deep red and cream coloured flowers wide, surrounded by six to twelve pinkish-cream bracts. The bracts curve over the flowers, forming a tulip-like head and leaving a small opening at, or a few millimetres above the soil surface. After pollination, each flower produces a fleshy, berry-like fruit containing up to 150 se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orchidaceae
Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering plants. The Orchidaceae have about 28,000 currently accepted species, distributed in about 763 genera. (See ''External links'' below). The determination of which family is larger is still under debate, because verified data on the members of such enormous families are continually in flux. Regardless, the number of orchid species is nearly equal to the number of bony fishes, more than twice the number of bird species, and about four times the number of mammal species. The family encompasses about 6–11% of all species of seed plants. The largest genera are ''Bulbophyllum'' (2,000 species), ''Epidendrum'' (1,500 species), ''Dendrobium'' (1,400 species) and ''Pleurothallis'' (1,000 species). It also includes ''Vanilla'' (the genus of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorophyll
Chlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words , ("pale green") and , ("leaf"). Chlorophyll allow plants to absorb energy from light. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion. Conversely, it is a poor absorber of green and near-green portions of the spectrum. Hence chlorophyll-containing tissues appear green because green light, diffusively reflected by structures like cell walls, is less absorbed. Two types of chlorophyll exist in the photosystems of green plants: chlorophyll ''a'' and ''b''. History Chlorophyll was first isolated and named by Joseph Bienaimé Caventou and Pierre Joseph Pelletier in 1817. The presence of magnesium in chlorophyll was discovered in 1906, and was that element's first detection in living tissue. After initial work done by German chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as regulatory sequences (see non-coding DNA), and often a substantial fraction of 'junk' DNA with no evident function. Almost all eukaryotes have mitochondria and a small mitochondrial genome. Algae and plants also contain chloroplasts with a chloroplast genome. The study of the genome is called genomics. The genomes of many organisms have been sequenced and various regions have been annotated. The International Human Genome Project reported the sequence of the genome for ''Homo sapiens'' in 200The Human Genome Project although the initial "finished" sequence was missing 8% of the genome consisting mostly of repetitive sequences. With advancements in technology that could handle sequenci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastid
The plastid (Greek: πλαστός; plastós: formed, molded – plural plastids) is a membrane-bound organelle found in the Cell (biology), cells of plants, algae, and some other eukaryotic organisms. They are considered to be intracellular endosymbiotic cyanobacteria. Examples include chloroplasts (used for photosynthesis), chromoplasts (used for pigment synthesis and storage), and leucoplasts (non-pigmented plastids that can sometimes differentiate). The event which led to permanent endosymbiosis in the Archaeplastida clade (of Embryophyte, land plants, red algae, and green algae) probably occurred with a cyanobiont (a symbiotic cyanobacteria) related to the genus ''Gloeomargarita lithophora, Gloeomargarita'', around 1.5 billion years ago. A later primary endosymbiosis event occurred in photosynthetic ''Paulinella'' amoeboids about 90–140 million years ago. This plastid belongs to the "PS-clade" (of the cyanobacteria genera ''Prochlorococcus'' and ''Synechococcus''). Chloroplas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehiscence (botany)
Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part; structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay or predation to release the contents. A similar process to dehiscence occurs in some flower buds (e.g., ''Platycodon'', ''Fuchsia''), but this is rarely referred to as dehiscence unless wikt:circumscissile, circumscissile dehiscence is involved; anthesis is the usual term for the opening of flowers. Dehiscence may or may not involve the loss of a structure through the process of abscission. The lost structures are said to be wikt:caducous, caducous. Association with crop breeding Manipulation of dehiscence can improve crop yield since a Trait (biological), trait that causes seed dispersal i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nectar
Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists, which in turn provide herbivore protection. Common nectar-consuming pollinators include mosquitoes, hoverflies, wasps, bees, butterflies and moths, hummingbirds, honeyeaters and bats. Nectar plays a crucial role in the foraging economics and evolution of nectar-eating species; for example, nectar foraging behavior is largely responsible for the divergent evolution of the African honey bee, ''A. m. scutellata'' and the western honey bee. Nectar is an economically important substance as it is the sugar source for honey. It is also useful in agriculture and horticulture because the adult stages of some predatory insects feed on nectar. For example, a number of parasitoid wasps (e.g. the social wasp species ''Apoica flavissima'') rely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal
Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal consonant, a consonant articulated with the back of the tongue * Dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ..., the fin located on the back of a fish or aircraft * Dorsal transcription factor, a maternally synthesized transcription factor {{disambig de:Dorsale fr:Dorsale it:Dorsale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral
Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction *Lateral cricoarytenoid muscle *Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral consonant, an l-like consonant in which air flows along the sides of the tongue **Lateral release (phonetics), the release of a plosive consonant into a lateral consonant Other uses *''Lateral'', journal of the Cultural Studies Association *Lateral canal, a canal built beside another stream *Lateral hiring, recruiting that targets employees of another organization *Lateral mark, a sea mark used in maritime pilotage to indicate the edge of a channel * Lateral stability of aircraft during flight *Lateral pass, a type of pass in American and Canadian football *Lateral support (other), various meanings *Lateral thinking, the solution of problems through an indirect and creative approach *Lateral number, a proposed alternate term for imagi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Column (botany)
The column, or technically the gynostemium, is a reproductive structure that can be found in several plant families: Aristolochiaceae, Orchidaceae, and Stylidiaceae. It is derived from the fusion of both male and female parts (stamens and pistil) into a single organ. The top part of the column is formed by the anther, which is covered by an anther cap. This means that the ''style'' and ''stigma'' of the pistil, with the filaments and one or more anthers, are all united. Orchidaceae The stigma sits at the apex of the column in the front but is pointing downwards after resupination (the rotation by 180 degrees before unfolding of the flower). This stigma has the form of a small bowl, the clinandrium, a viscous surface embedding the (generally) single anther. On top of it all is the anther cap. Sometimes there is a small extension or little beak to the median stigma lobe, called rostellum. Column wings may project laterally from the stigma. The column foot is formed by the atta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labellum (botany)
In botany, the labellum (or lip) is the part of the flower of an orchid or '' Canna'', or other less-known genera, that serves to attract insects, which pollinate the flower, and acts as a landing platform for them. ''Labellum'' (plural: ''labella'') is the Latin diminutive of ''labrum'', meaning lip. The labellum is a modified petal and can be distinguished from the other petals and from the sepals by its large size and its often irregular shape. It is not unusual for the other two petals of an orchid flower to look like the sepals, so that the labellum stands out as distinct. Bailey, L. H. ''Gentes Herbarum: Canna x orchiodes''. (Ithaca), 1 (3): 120 (1923); Khoshoo, T. N. & Guha, I. ''Origin and Evolution of Cultivated Cannas.'' Vikas Publishing House. In orchids, the labellum is the modified median petal that sits opposite from the fertile anther and usually highly modified from the other perianth segments. It is often united with the column and can be hinged or movable, fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
