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Commelineae
Commelineae is a Tribe (biology), tribe of monocotyledonous flowering plants in the dayflower family (biology), family (Commelinaceae). The tribe consists of 13 genera and about 350 species. It is one of two tribes in the subfamily Commelinoideae, the other being the Tradescantieae, which is made up of 26 genera and about 300 species. The remaining two genera in the family are in a separate subfamily, the Cartonematoideae. The Commelineae can be separated Morphology (biology), morphologically from its sister tribe, the Tradescantieae, through a number of technical characters. These include having six subsidiary cells with the terminal pair always being smaller than the second lateral pair, pollen with a spiny exine and a perforate pollen, tectum, primarily zygomorphic flowers, non-moniliform filament hairs, no silica in the Epidermis (botany), epidermis, and small chromosomes. Molecular phylogenetics generally supports the separation of the two tribes. References Comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commelinoideae
Commelinoideae is a subfamily of monocotyledonous plants in the dayflower family ( Commelinaceae). It is one of two subfamilies within the Commelinaceae and includes 39 genera (out of 41 in the family) and all but 12 of the family's several hundred known species. The subfamily is further broken down into two tribes, the Tradescantieae, which includes 26 genera and about 300 species, and the Commelineae, which contains 13 genera and about 350 species. The Commelinoideae is separated morphologically from the other subfamily, Cartonematoideae, in having glandular microhairs, arteries containing needle-like calcium oxalate crystals called raphide canals in between the veins of the leaves, and flowers that are virtually never both yellow and actinomorphic. Molecular phylogenetics also supports the separation of the two subfamilies. Phylogeny The following is a phylogeny, or evolutionary tree, of most of the genera in Commelinoideae based on DNA sequences from the plastid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyspatha
''Polyspatha'' is a genus of perennial monocotyledonous flowering plants in the family Commelinaceae. It is restricted to tropical Africa consists of three recognized species. The genus is characterised by its unique leaf-like bracts that subtend inflorescences (often called spathes), which are arranged oppositely up the flowering shoot. Plants in the genus also have white flowers, two carpels with one seed in each, and vegetative reproduction by stolons. Along with most other genera of the Commelineae Commelineae is a Tribe (biology), tribe of monocotyledonous flowering plants in the dayflower family (biology), family (Commelinaceae). The tribe consists of 13 genera and about 350 species. It is one of two tribes in the subfamily Commelinoideae ... tribe with relatively few species, ''Polyspatha'' is found in tropical forest understories, and also in disturbed shady locations. ; Species * '' Polyspatha paniculata'' Benth. - western + central Africa from Sierra Leone to Zaire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commelinaceae
Commelinaceae is a family of flowering plants. In less formal contexts, the group is referred to as the dayflower family or spiderwort family. It is one of five families in the order Commelinales and by far the largest of these with about 731 known species in 41 genera. Well known genera include '' Commelina'' (dayflowers) and '' Tradescantia'' (spiderworts). The family is diverse in both the Old World tropics and the New World tropics, with some genera present in both. The variation in morphology, especially that of the flower and inflorescence, is considered to be exceptionally high amongst the angiosperms. The family has always been recognized by most taxonomists. The APG III system of 2009 (unchanged from the APG system of 1998), also recognizes this family, and assigns it to the order Commelinales in the clade commelinids in the monocots. The family counts several hundred species of herbaceous plants. Many are cultivated as ornamentals. The stems of these plants are g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commelina Maculata
''Commelina maculata'' is an herbaceous plant in the dayflower family found in India, Burma, Bhutan, and southern China. It is most often encountered along forest margins, in grasslands, along roadsides, or in moist ditches. The species is characterized by its short-stalked spathe In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or o ...s with fused margins that usually occur in clusters of two or three, bearing flowers that barely stick out from the mouth of the spathe. The species is very similar to '' Commelina paludosa'', and further study is needed to recognize the boundary between the two. The two are typically differentiated on the basis of ''C. paludosa'' having larger and more numerous spathes that occur in clusters of four to ten, forming a sort of head. ''C. paludosa'' is also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tribe (biology)
In biology, a tribe is a taxonomic rank above genus, but below family (biology), family and subfamily. It is sometimes subdivided into subtribes. By convention, all taxonomic ranks from genus upwards 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 Goat-antelope#Tribe Caprini, 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 Scilloideae#Hyacintheae, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated (S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epidermis (botany)
The epidermis (from the Greek ''ἐπιδερμίς'', meaning "over-skin") is a single layer of cells that covers the leaves, flowers, roots and stems of plants. It forms a boundary between the plant and the external environment. The epidermis serves several functions: it protects against water loss, regulates gas exchange, secretes metabolic compounds, and (especially in roots) absorbs water and mineral nutrients. The epidermis of most leaves shows dorsoventral anatomy: the upper (adaxial) and lower (abaxial) surfaces have somewhat different construction and may serve different functions. Woody stems and some other stem structures such as potato tubers produce a secondary covering called the periderm that replaces the epidermis as the protective covering. Description The epidermis is the outermost cell layer of the primary plant body. In some older works the cells of the leaf epidermis have been regarded as specialized parenchyma cells,Hill, J. Ben; Overholts, Lee O; Pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomorphic
Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirally arranged. Actinomorphic Most flowers are actinomorphic ("star shaped", "radial"), meaning they can be divided into 3 or more identical sectors which are related to each other by rotation about the center of the flower. Typically, each sector might contain one tepal or one petal and one sepal and so on. It may or may not be possible to divide the flower into symmetrical halves by the same number of longitudinal planes passing through the axis: Oleander is an example of a flower without such mirror planes. Actinomorphic flowers are also called radially symmetrical or regular flowers. Other examples of actinomorphic flowers are the lily (''Lilium'', Liliaceae) and the buttercup ('' Ranunculus'', Ranunculaceae). Zygomorphic Zygo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exine
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance ( shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
