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Tradescantia
''Tradescantia'' () is a genus of 85 species of herbaceous perennial wildflowers in the family Commelinaceae, native to the Americas from southern Canada to northern Argentina, including the West Indies. Members of the genus are known by many common names, including inchplant, wandering jew, spiderwort, dayflower and trad. ''Tradescantia'' grow , and are commonly found individually or in clumps in wooded areas and open fields. They were introduced into Europe as ornamental plants in the 17th century and are now grown in many parts of the world. Some species have become naturalized in regions of Europe, Asia, Africa, and Australia, and on some oceanic islands. The genus's many species are of interest to cytogenetics because of evolutionary changes in the structure and number of their chromosomes. They have also been used as bioindicators for the detection of environmental mutagens. Some species have become pests to cultivated crops and considered invasive. Description ''Tradesc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tradescantia Ohiensis
''Tradescantia ohiensis'', commonly known as bluejacket or Ohio spiderwort, is an herbaceous plant species in the genus ''Tradescantia'' native to eastern and central North America. It is the most common and widely distributed species of ''Tradescantia'' in the United States, where it can be found from Maine in the northeast, west to Minnesota, and south to Texas and Florida. It also has a very small distribution in Canada in extreme southern Ontario near Windsor.Turner, B.L. (2006). Texas species of ''Tradescantia'' (Commelinaceae). Phytologia 88: 312-331. Distinguishing features of the species include glaucous ''Glaucous'' (, ) is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the glaucous gull (''Larus hyperboreus''), glaucous-winged gull (''Larus glaucescens''), ... leaves and stems, leaves forming an acute angle with the stems, sepals with hairs lacking glands which are confined to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tradescantia Virginiana
''Tradescantia virginiana'', the Virginia spiderwort, is a species of flowering plant in the family Commelinaceae (the spiderwort family). It is the type species of the genus '' Tradescantia'', native to the eastern United States. Common names include Virginia spiderwort, common spiderwort, lady’s tears, and spider lily. Description Virginia spiderwort is an herbaceous, perennial, clump-forming plant that is native to eastern and central United States and Ontario, Canada. It is considered a wildflower, and whole plant habits include arching, clumping, erect, and spreading. This species arises from a cluster of stout, overwintering roots. It spreads through underground stems to form large colonies. The plant can grow 1.5-3 feet tall and 1-1.5 feet wide. Stems of this species are commonly clumped but may be solitary. They can be smooth or have scattered, short hairs and usually grow unbranched. Each stem has 2-5 leaves attached by a leaf sheath that is one to three centimeters ... [...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 gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perennial Plant
In horticulture, the term perennial (''wikt:per-#Prefix, per-'' + ''wikt:-ennial#Suffix, -ennial'', "through the year") is used to differentiate a plant from shorter-lived annual plant, annuals and biennial plant, biennials. It has thus been defined as a plant that lives more than 2 years. The term is also loosely used to distinguish plants with little or no woody growth (secondary growth in Tree girth measurement, girth) from trees and shrubs, which are also technically ''perennials''. Notably, it is estimated that 94% of plant species fall under the category of perennials, underscoring the prevalence of plants with lifespans exceeding two years in the botanical world. Perennials (especially small flowering plants) that grow and bloom over the spring and summer, die back every autumn and winter, and then return in the spring from their rootstock or other overwintering structure, are known as Herbaceous plant, herbaceous perennials. However, depending on the rigours of the loca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutagen
In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer in animals, such mutagens can therefore be carcinogens, although not all necessarily are. All mutagens have characteristic mutational signatures with some chemicals becoming mutagenic through cellular processes. The process of DNA becoming modified is called mutagenesis. Not all mutations are caused by mutagens: so-called "spontaneous mutations" occur due to spontaneous hydrolysis, errors in DNA replication, repair and recombination. Discovery The first mutagens to be identified were carcinogens, substances that were shown to be linked to cancer. Tumors were described more than 2,000 years before the discovery of chromosomes and DNA; in 500 B.C., the Greek physician Hippocrates named tumors resembling a crab ''karkinos'' (from which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytogenetics
Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis and meiosis. Techniques used include Karyotype, karyotyping, analysis of G banding, G-banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as Fluorescence in situ hybridization, fluorescence ''in situ'' hybridization (FISH) and comparative genomic hybridization (CGH). History Beginnings Chromosomes were first observed in plant cells by Carl Nägeli in 1842. Their behavior in animal (salamander) cells was described by Walther Flemming, the discoverer of mitosis, in 1882. The name was coined by another German anatomist, Heinrich Wilhelm Gottfried von Waldeyer-Hartz, von Waldeyer in 1888. The next stage took place after the development of genetics in the early 20th century, when it was appreciated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most important of these proteins are the histones. Aided by chaperone proteins, the histones bind to and condense the DNA molecule to maintain its integrity. These eukaryotic chromosomes display a complex three-dimensional structure that has a significant role in transcriptional regulation. Normally, chromosomes are 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 stage occurs, each chromosome is duplicated ( S phase), and the two copies are joined by a centromere—resulting in either an X-shaped structure if the centromere is located equatorially, or a two-armed structure if the centromere is located distally; the jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioindicator
A bioindicator is any species (an indicator species) or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other small water crustaceans that are present in many water bodies can be monitored for changes (biochemical, physiological, or behavioural) that may indicate a problem within their ecosystem. Bioindicators can tell us about the cumulative effects of different pollutants in the ecosystem and about how long a problem may have been present, which physical and chemical testing cannot. A biological monitor or biomonitor is an organism that provides quantitative information on the quality of the environment around it. Therefore, a good biomonitor will indicate the presence of the pollutant and can also be used in an attempt to provide additional information about the amount and intensity of the exposure. A biological indicator is also the name gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Environment
The natural environment or natural world encompasses all life, biotic and abiotic component, abiotic things occurring nature, naturally, meaning in this case not artificiality, artificial. The term is most often applied to Earth or some parts of Earth. This environment encompasses the interaction of all living species, climate, weather and natural resources that affect human survival and economic activity. The concept of the ''natural environment'' can be distinguished as components: * Complete ecological units that function as natural systems without massive civilized human intervention, including all vegetation, microorganisms, soil, rock (geology), rocks, plateaus, mountains, the atmosphere of Earth, atmosphere and list of natural phenomena, natural phenomena that occur within their boundaries and their nature. * Universal natural resources and phenomenon, physical phenomena that lack clear-cut boundaries, such as air, water and climate, as well as energy, radiation, electric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pest (organism)
A pest is any organism harmful to humans or human concerns. The term is particularly used for creatures that damage crops, livestock, and forestry or cause a nuisance to people, especially in their homes. Humans have modified the environment for their own purposes and are intolerant of other creatures occupying the same space when their activities impact adversely on human objectives. Thus, an elephant is unobjectionable in its natural habitat but a pest when it tramples crops. Some animals are disliked because they bite or sting; wolves, snakes, wasps, ants, bed bugs, fleas and ticks belong in this category. Others enter the home; these include houseflies, which land on and contaminate food; beetles, which tunnel into the woodwork; and other animals that scuttle about on the floor at night, like rats and cockroaches, which are often associated with unsanitary conditions. Agricultural and horticultural crops are attacked by a wide variety of pests, the most important being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cultivated Crop
A crop is a plant that can be grown and harvested extensively for profit or subsistence. In other words, a crop is a plant or plant product that is grown for a specific purpose such as food, fibre, or fuel. When plants of the same species are cultivated in rows or other systematic arrangements, it is called crop field or crop cultivation. Most crops are harvested as food for humans or fodder for livestock. Important non-food crops include horticulture, floriculture, and industrial crops. Horticulture crops include plants used for other crops (e.g. fruit trees). Floriculture crops include bedding plants, houseplants, flowering garden and pot plants, cut cultivated greens, and cut flowers. Industrial crops are produced for clothing (fiber crops e.g. cotton), biofuel (energy crops, algae fuel), or medicine (medicinal plants). Production There was an increase in global production of primary crops by 56% between 2000 and 2022 to 9.6 billion tonnes, which represents a 0.7% com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
