HOME





Single Access Key
In phylogenetics, a single-access key (also called dichotomous key, sequential key, analytical key, or pathway key) is an identification key where the sequence and structure of identification steps is fixed by the author of the key. At each point in the decision process, multiple alternatives are offered, each leading to a result or a further choice. The alternatives are commonly called "leads", and the set of leads at a given point a "couplet". Single access keys are closely related to decision trees and binary search trees. However, to improve the usability and reliability of keys, many single-access keys incorporate reticulation, changing the tree structure into a directed acyclic graph. Single-access keys have been in use for several hundred years. They may be printed in various styles (e. g., linked, nested, indented, graphically branching) or used as interactive, computer-aided keys. In the latter case, either a longer part of the key may be displayed (optionally hype ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Phylogenetics
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and morphology. The results are a phylogenetic tree—a diagram depicting the hypothetical relationships among the organisms, reflecting their inferred evolutionary history. The tips of a phylogenetic tree represent the observed entities, which can be living taxa or fossils. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the taxa represented on the tree. An unrooted tree diagram (a network) makes no assumption about directionality of character state transformation, and does not show the origin or "root" of the taxa in question. In addition to their use for inferring phylogenetic pa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Flower
Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, modified leaves; corolla, the petals; androecium, the male reproductive unit consisting of stamens and pollen; and gynoecium, the female part, containing style and stigma, which receives the pollen at the tip of the style, and ovary, which contains the ovules. When flowers are arranged in groups, they are known collectively as inflorescences. Floral growth originates at stem tips and is controlled by MADS-box genes. In most plant species flowers are heterosporous, and so can produce sex cells of both sexes. Pollination mediates the transport of pollen to the ovules in the ovaries, to facilitate sexual reproduction. It can occur between different plants, as in cross-pollination, or between flowers on the same plant or even the same f ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


Red Oaks
''Red Oaks'' is an American comedy drama television series created by Joe Gangemi and Gregory Jacobs. The first season was released on Amazon Prime Video on October 9, 2015. On December 18, 2015, Amazon announced that the show would be returning for a second season in 2016. The second season was released on November 11, 2016. On January 30, 2017, Amazon announced that the series was renewed for a third and final season, which was released on October 20, 2017. Plot David, a college student, begins working at Red Oaks, a Jewish country club in New Jersey during his summer break in 1985. The show follows David's life, with numerous subplots including his family, friends, and coworkers, and primarily revolves around the club. The show explores themes such as adolescence, relationships, socioeconomic mobility, and the pursuit of happiness in a mostly comedic fashion against the backdrop of the New York–New Jersey area in the 1980s. Cast Main Recurring Episodes Season 1 (20 ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Live Oak
Live oak or evergreen oak is any of a number of oaks in several different sections of the genus ''Quercus'' that share the characteristic of evergreen foliage. These oaks are generally not more closely related to each other than they are to other oaks. When the term live oak is used in a specific rather than general sense, it most commonly refers to the group of species under ''Quercus'' sect. ''Virentes'', which includes the southern live oak (''Quercus virginiana''), the first species so named, and an icon of the Old South. The name ''live oak'' comes from the fact that evergreen oaks remain green and "live" throughout winter, when other oaks are dormant and leafless. The name is used mainly in North America, where evergreen oaks are widespread in warmer areas along the Atlantic coast from southeast Virginia to Florida, west along the Gulf Coast to Louisiana and Mexico, and across the southwest to California. Evergreen oak species are also common in parts of southern Eu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


Swamp Chestnut Oak
''Quercus michauxii'', the swamp chestnut oak, is a species of oak in the white oak section ''Quercus'' section ''Quercus'' in the beech family. It is native to bottomlands and wetlands in the southeastern and midwestern United States, in coastal states from New Jersey to Texas, inland primarily in the Mississippi–Ohio Valley as far as Oklahoma, Missouri, Illinois, and Indiana. Description The leaves of the swamp chestnut oak are simple (not compound), long and broad, with 15–20 lobe-like, rounded simple teeth on each side, similar to those of chestnut oak and chinkapin oak (''Quercus muehlenbergii''), although they generally do not achieve the more slender form that the leaves of those trees may exhibit at times. The leaves turn red in autumn. The fruit is an acorn long and broad, borne on a 2–3 cm peduncle, maturing in the fall, about 6 months after pollination. The tree only bears heavy acorn crops at intervals of several years. Taxonomy The swamp chestnu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Quercus Alba
''Quercus alba'', the white oak, is one of the preeminent hardwoods of eastern and central North America. It is a long-lived oak, native to eastern and central North America and found from Minnesota, Ontario, Quebec, and southern Maine south as far as northern Florida and eastern Texas. Specimens have been documented to be over 450 years old. Although called a white oak, it is very unusual to find an individual specimen with white bark; the usual colour is a light gray. The name comes from the colour of the finished wood. In the forest it can reach a magnificent height and in the open it develops into a massive broad-topped tree with large branches striking out at wide angles. Description ''Quercus alba'' typically reaches heights of at maturity, and its canopy can become quite massive as its lower branches are apt to extend far out laterally, parallel to the ground. Trees growing in a forest will become much taller than ones in an open area which develop to be short and mass ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Northern Red Oak
''Quercus rubra'', the northern red oak, is an oak tree in the red oak group (''Quercus'' section ''Lobatae''). It is a native of North America, in the eastern and central United States and southeast and south-central Canada. It has been introduced to small areas in Western Europe, where it can frequently be seen cultivated in gardens and parks. It prefers good soil that is slightly acidic. Often simply called red oak, northern red oak is so named to distinguish it from southern red oak (''Q. falcata''), also known as the Spanish oak. Northern red oak is sometimes called champion oak. Description In many forests, ''Quercus rubra'' grows straight and tall, to , exceptionally to tall, with a trunk of up to in diameter. Open-grown trees do not get as tall, but can develop a stouter trunk, up to in diameter. It has stout branches growing at right angles to the stem, forming a narrow round-topped head. Under optimal conditions and full sun, northern red oak is fast growing ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


Blackjack Oak
''Quercus marilandica'', the blackjack oak, is a small oak, one of the red oak group ''Quercus'' sect. ''Lobatae''. It is native to the eastern and central United States. Description ''Quercus marilandica'' is a small deciduous tree growing to tall, with bark cracked into rectangular black plates with narrow orange fissures. The leaves are long and broad, and typically flare from a tapered base to a broad three-lobed bell shape with only shallow indentations. They are dark green and glossy above, pubescent underneath, and often remain attached to the twigs through the winter after turning colors from red to brown in the fall. The acorn is small, long and broad; like those of other red oaks, it takes 18 months to mature. Blackjack oaks in the Cross Timbers can grow from high but seldom reach more than , with a trunk diameter of . The leaves are from in length and about the same width. Distribution and habitat The blackjack oak can be found from Long Island in New Yor ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]




Shingle Oak
''Quercus imbricaria'', the shingle oak, is a deciduous tree in the red oak group of oaks. It is native primarily to the Midwestern and Upper South regions of North America. Description Quercus imbricaria is usually high, maximum height 100 ft, with a broad pyramidal head when young, becoming in old age, broad-topped and open. Trunk up to in diameter (rarely 1.4 m or 56 in). It reaches its largest size in southern Illinois and Indiana, although the national champion is 104' by 68' in Cincinnati, Ohio. * Bark: Light brown, scaly; on young stems light brown, smooth. Branchlets slender, dark green and shining at first, later become light brown, finally dark brown. * Wood: Pale reddish brown, sapwood lighter; heavy, hard coarse-grained, checks badly in drying; used for shingles and sometimes in construction. Sp. gr., 0.7529; weight of cu. ft., 46.92 lbs. * Winter buds: Light brown, ovate, acute, one-eight inch long. * Leaves: Alternate, oblong or obovate, f ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


Willow Oak
''Quercus phellos'', the willow oak, is a North American species of a deciduous tree in the red oak group of oaks. It is native to the south-central and eastern United States. Description It is a medium-sized tree growing to tall (exceptionally to ), with a trunk up to in diameter (exceptionally ). It is distinguished from most other oaks by its leaves, which are shaped like willow leaves, long and broad with an entire (untoothed and unlobed) margin; they are bright green above, paler beneath, usually hairless but sometimes downy beneath. The fruit is an acorn, long, and almost as wide as long, with a shallow cup; it is one of the most prolific producers of acorns. The tree starts acorn production around 15 years of age, earlier than many oak species. Willow oaks can grow moderately fast (height growth up to a year), and tend to be conic to oblong when young, rounding out and gaining girth at maturity (i.e. more than 50 years). Distribution and habitat The species i ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Dwarf Live Oak
''Quercus minima'', the dwarf live oak or minimal oak, is a North American species of shrubs in the beech family. It is native to the southeastern United States. It is placed in the southern live oaks section of the genus ''Quercus'' ( section ''Virentes''). Description ''Quercus minima'' is an evergreen or semi-evergreen shrub rarely more than tall, reproducing by seed and also by means of underground rhizomes. It commonly forms extensive cloned colonies with many stems, many of them unbranched. The leaves are alternate, up to long, and toothless or with irregular teeth or lobes. The lobes, when present, are usually spine-tipped. The leaves are retained through the winter, dropping just before or as new growth resumes in late winter or early spring. Distribution ''Quercus minima'' is native to the coastal plain of the southeastern United States, primarily in Florida but extending from there to the Carolinas and eastern Louisiana. There are reports of the species also growi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]


picture info

Southern Live Oak
''Quercus virginiana'', also known as the southern live oak, is an evergreen oak tree endemic to the Southeastern United States. Though many other species are loosely called live oak, the southern live oak is particularly iconic of the Old South. Many very large and old specimens of live oak can be found today in the Deep South region of the United States. Description Although live oaks retain their leaves nearly year-round, they are not true evergreens. Live oaks drop their leaves immediately before new leaves emerge in the spring. Occasionally, Senescence, senescing leaves may turn yellow or contain brown spots in the winter, leading to the mistaken belief that the tree has oak wilt, whose symptoms typically occur in the summer. A live oak's defoliation may occur sooner in marginal climates or in dry or cold winters. The Bark (botany), bark is dark, thick, and furrowed longitudinally. The leaves are stiff and leathery, with the tops shiny dark green and the bottoms pale gra ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   [Amazon]