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Canellales Genera
Canellales is the botanical name for an order of flowering plants, one of the four orders of the magnoliids. It is recognized by the most recent classification of flowering plants, the APG IV system. It is defined to contain two families: Canellaceae and Winteraceae, which comprise 136 species of fragrant trees and shrubs. The Canellaceae are found in tropical America and Africa, and the Winteraceae are part of the Antarctic flora (found in diverse parts of the southern hemisphere). Although the order was defined based on phylogenetic studies, a number of possible synapomorphies have been suggested, relating to the pollen tube, the seeds, the thickness of the integument, and other aspects of the morphology. Until 1999, these two families were not considered to be closely related. Instead the Winteraceae were considered to be a primitive family (due to the structure of the xylem and carpel, a structure which now seems to be derived from xylem and carpels more typical of the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur John Cronquist
Arthur John Cronquist (March 19, 1919 – March 22, 1992) was an American biologist, botanist and a specialist on Compositae. He is considered one of the most influential botanists of the 20th century, largely due to his formulation of the Cronquist system as well as being the primary co-author to the Flora of the Pacific Northwest, still the most up to date flora for three northwest U.S. States to date. Two plant genera in the aster family have been named in his honor. These are ''Cronquistia'', a possible synonym of '' Carphochaete'', and ''Cronquistianthus'', which is sometimes included as a group within ''Eupatorium''. The former was applied by R.M. King and the latter by him and Harold E. Robinson. Life Arthur Cronquist was born on March 19, 1919, in San Jose, California, but he grew up outside of Portland, Oregon, as well as in Pocatello, Idaho. His parents divorced when he was young and he and his older sister were brought up by his mother, who worked for the Union ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Morphology
Phytomorphology is the study of the morphology (biology), physical form and external structure of plants.Raven, P. H., R. F. Evert, & S. E. Eichhorn. ''Biology of Plants'', 7th ed., page 9. (New York: W. H. Freeman, 2005). . This is usually considered distinct from plant anatomy, which is the study of the internal Anatomy, structure of plants, especially at the microscopic level. Plant morphology is useful in the visual identification of plants. Recent studies in molecular biology started to investigate the molecular processes involved in determining the conservation and diversification of plant morphologies. In these studies transcriptome conservation patterns were found to mark crucial ontogenetic transitions during the plant life cycle which may result in evolutionary constraints limiting diversification. Scope Plant morphology "represents a study of the development, form, and structure of plants, and, by implication, an attempt to interpret these on the basis of similarit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetics
In biology, phylogenetics (; from Greek language, Greek wikt:φυλή, φυλή/wikt:φῦλον, φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, Protein, protein Amino acid, amino acid sequences, or Morphology (biology), morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnoliales
The Magnoliales are an order of flowering plants. Classification The Magnoliales include six families: * Annonaceae (custard apple family, over 2000 species of trees, shrubs, and lianas; mostly tropical but some temperate) * Degeneriaceae (two species of trees found on Pacific islands) * Eupomatiaceae (two species of trees and shrubs found in New Guinea and eastern Australia) * Himantandraceae (two species of trees and shrubs, found in tropical areas in Southeast Asia and Australia) * Magnoliaceae (about 225 species including magnolias and tulip trees) * Myristicaceae (several hundred species including nutmeg) APG system The APG system (1998), APG II system (2003), APG III system (2009), and APG IV system (2016) place this order in the clade magnoliids, circumscribed as follows: In these systems, published by the APG, the Magnoliales are a basal group, excluded from the eudicots. Earlier systems The Cronquist system (1981) placed the order in the subclass Magnoliidae of cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laurales
The Laurales are an order of flowering plants. They are magnoliids, related to the Magnoliales. The order includes about 2500-2800 species from 85-90 genera, which comprise seven families of trees and shrubs. Most of the species are tropical and subtropical, though a few genera reach the temperate zone. The best known species in this order are those of the Lauraceae (for example bay laurel, cinnamon, avocado, and ''Sassafras''), and the ornamental shrub ''Calycanthus'' of the Calycanthaceae. The earliest lauraceous fossils are from the early Cretaceous. It is possible that the ancient origin of this order is one of the reasons for its highly diverged morphology. Presently no single morphological property is known, which would unify all the members of Laurales. The presently accepted classification is based on molecular and genetic analysis. Classification The first botanist to think of the Laurales as a natural group was H. Hallier in 1905. He viewed them as being derived from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperales
Piperales is an order of flowering plants (4,170 recognized species). It necessarily includes the family Piperaceae but other taxa have been included or disincluded variously over time. Well-known plants which may be included in this order include black pepper, kava, pepper elder, lizard's tail, birthwort, and wild ginger. Classification APG system In the APG IV system, of 2016, this order is placed in the clade magnoliids and is circumscribed as follows: *order Piperales *: family Aristolochiaceae (including Asaraceae, Hydnoraceae and Lactoridaceae) *: family Piperaceae *: family Saururaceae This is an expansion from the APG system, of 1998, which used the same placement (in the magnoliids) but used this circumscription: * order Piperales'' *: family Aristolochiaceae *: family Lactoridaceae *: family Piperaceae *: family Saururaceae Earlier systems The Cronquist system, of 1981, placed the order in the subclass Magnoliidae of class Magnoliopsida dicotyledonsand used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnoliids
Magnoliids (or Magnoliidae or Magnolianae) are a clade of flowering plants. With more than 10,000 species, including magnolias, nutmeg, bay laurel, cinnamon, avocado, black pepper, tulip tree and many others, it is the third-largest group of angiosperms after the eudicots and monocots. The group is characterized by trimerous flowers, pollen with one pore, and usually branching-veined leaves. Some members of the subclass are among the earliest angiosperms and share anatomical similarities with gymnosperms like stamens that resemble the male cone scales of conifers and carpels found on the long flowering axis. Classification "Magnoliidae" is the botanical name of a subclass, and "magnoliids" is an informal name that does not conform to the International Code of Nomenclature for algae, fungi, and plants. The circumscription of a subclass will vary with the taxonomic system being used. The only requirement is that it must include the family Magnoliaceae. The informal name "magnoliids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Phylogeny
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 framew ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myristicaceae
The Myristicaceae are a family of flowering plants native to Africa, Asia, Pacific islands, and the Americas and has been recognized by most taxonomists. It is sometimes called the "nutmeg family", after its most famous member, ''Myristica fragrans'', the source of the spices nutmeg and mace. The best known genera are ''Myristica'' in Asia and ''Virola'' in the Neotropics. The family consists of about 21 genera with about 520 species of trees, shrubs and rarely lianas ('' Pycnanthus'') found in tropical forests around the world. Most of the species are large trees that are valued in the timber industry. Description They are typically trees with reddish sap and distinctive pagoda-like growth (known as myristicaceous branching) in which horizontal branching only occurs at certain nodes along the main axis of the trunk, each node separated by a large gap where no branching occurs. All genera are dioecious, except ''Endocomia'' and some ''Iryanthera''. The inner bark is usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpel
Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' and is typically surrounded by the pollen-producing reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes (i.e. egg cells), the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells. The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on a gametophyte shoot in mosses, liverworts, and hornworts. The corresponding terms for the male parts of those plants are clusters of antheridia within the androecium. Flowers that bear a gynoecium but no stamens are called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylem
Xylem is one of the two types of transport tissue in vascular plants, the other being phloem. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients. The word ''xylem'' is derived from the Ancient Greek word (''xylon''), meaning "wood"; the best-known xylem tissue is wood, though it is found throughout a plant. The term was introduced by Carl Nägeli in 1858. Structure The most distinctive xylem cells are the long tracheary elements that transport water. Tracheids and vessel elements are distinguished by their shape; vessel elements are shorter, and are connected together into long tubes that are called ''vessels''. Xylem also contains two other type of cells: parenchyma and fibers. Xylem can be found: * in vascular bundles, present in non-woody plants and non-woody parts of woody plants * in secondary xylem, laid down by a meristem called the vascular cambium in woody plants * as part of a stelar arrangement n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integument
In biology, an integument is the tissue surrounding an organism's body or an organ within, such as skin, a husk, shell, germ or rind. Etymology The term is derived from ''integumentum'', which is Latin for "a covering". In a transferred, or figurative sense, it could mean a cloak or a disguise. In English, "integument" is a fairly modern word, its origin having been traced back to the early seventeenth century; and refers to a material or layer with which anything is enclosed, clothed, or covered in the sense of "clad" or "coated", as with a skin or husk. Botanical usage In botany, the term "integument" may be used as it is in zoology, referring to the covering of an organ. When the context indicates nothing to the contrary, the word commonly refers to an envelope covering the nucellus of the ovule. The integument may consist of one layer (unitegmic) or two layers (bitegmic), each of which consisting of two or more layers of cells. The integument is perforated by a pore, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
