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Dahlia Day - Geograph
Dahlia (, ) is a genus of bushy, tuberous, herbaceous perennial plants native to Mexico and Central America. A member of the Asteraceae (former name: Compositae) family of dicotyledonous plants, its garden relatives thus include the sunflower, daisy, chrysanthemum, and zinnia. There are 49 species of this genus, with hybrids commonly grown as garden plants. Flower forms are variable, with one head per stem; these can be as small as diameter or up to ("dinner plate"). This great variety results from dahlias being octoploids—that is, they have eight sets of homologous chromosomes, whereas most plants have only two. In addition, dahlias also contain many transposons—genetic pieces that move from place to place upon an allele—which contributes to their manifesting such great diversity. The stems are leafy, ranging in height from as low as to more than . The majority of species do not produce scented flowers. Like most plants that do not attract pollinating insects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dalea
''Dalea'' is a genus of flowering plants in the legume family, Fabaceae. Members of the genus are commonly known as prairie clover or indigo bush. Its name honors English apothecary Samuel Dale (1659–1739). They are native to the Western hemisphere, where they are distributed from Canada to Argentina. Nearly half of the known species are endemic to Mexico. Two species of ''Dalea'' (''Dalea ornata'' and ''Dalea searlsiae'') have been considered for rangeland restoration. Species ''Dalea'' comprises the following species: * ''Dalea abietifolia'' (Rydb.) Bullock * ''Dalea acracarpica'' Barneby * ''Dalea adenopoda'' (Rydb.) Isely—Tampa prairie clover * ''Dalea aenigma'' Barneby * ''Dalea albiflora'' A. Gray—whiteflower prairie clover * ''Dalea ananassa'' Barneby * ''Dalea antana'' J.F. Macbr. * ''Dalea arenicola'' (Wemple) B.L. Turner * ''Dalea aurea'' C. Fraser—golden prairie clover * ''Dalea austrotexana'' B.L.Turner * '' Dalea ayavacensis'' Kunth * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octoploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by meiosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petal
Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually accompanied by another set of modified leaves called sepals, that collectively form the ''calyx'' and lie just beneath the corolla. The calyx and the corolla together make up the perianth, the non-reproductive portion of a flower. When the petals and sepals of a flower are difficult to distinguish, they are collectively called tepals. Examples of plants in which the term ''tepal'' is appropriate include Genus, genera such as ''Aloe'' and ''Tulipa''. Conversely, genera such as ''Rose, Rosa'' and ''Phaseolus'' have well-distinguished sepals and petals. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly colored tepals. Sinc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floret
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology. For other related terms, see Glossary of phytopathology, Glossary of lichen terms, and List of Latin and Greek words commonly used in systematic names. A B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with Thailand, Myanmar, and Indonesia. Modern humans arrived on the Indian subcontinent from Africa no later than 55,000 years ago., "Y-Chromosome and Mt-DNA data support the colonization of South Asia by modern humans originating in Africa. ... Coalescence dates for most non-European populations average to between 73–55 ka.", "Modern human beings—''Homo sapiens''—originated in Africa. Then, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute Of Technology Agartala
National Institute of Technology Agartala (NIT Agartala or NITA) is a technology-oriented institute of higher education established by India's Ministry of Human Resource Development Government of India in Agartala, India. It was founded as Tripura Engineering College in 1965 and declared a National Institute of Technology (NIT) in 2006, thus being recognized as an Institute of National Importance. The institute was established in 1965 as Tripura Engineering College, with the branches of civil, electrical, and mechanical engineering. It was initially affiliated with Calcutta University and had the same curriculum structure and examination system as Bengal Engineering College (currently IIEST Shibpur). After the establishment of Tripura University in 1987, the institute was affiliated with it. Courses toward a degree in computer science and engineering were offered beginning in the 1999–2000 session, and three new degrees were offered beginning in the 2005–06 session: Electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spanish Conquest Of The Aztec Empire
The Spanish conquest of the Aztec Empire, also known as the Conquest of Mexico or the Spanish-Aztec War (1519–21), was one of the primary events in the Spanish colonization of the Americas. There are multiple 16th-century narratives of the events by Spanish conquistadors, their indigenous allies, and the defeated Aztecs. It was not solely a contest between a small contingent of Spaniards defeating the Aztec Empire but rather the creation of a coalition of Spanish invaders with tributaries to the Aztecs, and most especially the Aztecs' indigenous enemies and rivals. They combined forces to defeat the Mexica of Tenochtitlan over a two-year period. For the Spanish, the expedition to Mexico was part of a project of Spanish colonization of the New World after twenty-five years of permanent Spanish settlement and further exploration in the Caribbean. Significant events in the conquest of Mesoamerica Historical sources for the conquest of Mexico recount some of the same events in bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aztecs
The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different Indigenous peoples of Mexico, ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl, Nahuatl language and who dominated large parts of Mesoamerica from the 14th to the 16th centuries. Aztec culture was organized into city-states (''altepetl''), some of which joined to form alliances, political confederations, or empires. The Aztec Empire was a confederation of three city-states established in 1427: Tenochtitlan, city-state of the Mexica or Tenochca; Texcoco (altepetl), Texcoco; and Tlacopan, previously part of the Tepanec empire, whose dominant power was Azcapotzalco (altepetl), Azcapotzalco. Although the term Aztecs is often narrowly restricted to the Mexica of Tenochtitlan, it is also broadly used to refer to Nahuas, Nahua polities or peoples of central Pre-Columbian Mexico, Mexico in the preh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatemala, Belize, and the Caribbean Sea; and to the east by the Gulf of Mexico. Mexico covers ,Mexico ''''. . making it the world's 13th-largest country by are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floral Emblem
In a number of countries, plants have been chosen as symbols to represent specific geographic areas. Some countries have a country-wide floral emblem; others in addition have symbols representing subdivisions. Different processes have been used to adopt these symbols – some are conferred by government bodies, whereas others are the result of informal public polls. The term floral emblem, which refers to flowers specifically, is primarily used in Australia and Canada. In the United States, the term state flower is more often used. National plants Africa Mauritius The national flower of Mauritius is '' Trochetia boutoniana''. Seychelles The national flower of the Seychelles is the tropicbird orchid (known locally as ''orkid payanke''), '' Angraecum eburneum''. South Africa The national flower of South Africa is the King Protea, ''Protea cynaroides''. Tunisia The national flower of Tunisia is jasmine. It was chosen as a symbol for the 2010 Tunisian Revolution. Asia Ban ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollination
Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds, and bats; water; wind; and even plants themselves, when self-pollination occurs within a closed flower. Pollination often occurs within a species. When pollination occurs between species, it can produce hybrid offspring in nature and in plant breeding work. In angiosperms, after the pollen grain (gametophyte) has landed on the stigma, it germinates and develops a pollen tube which grows down the style until it reaches an ovary. Its two gametes travel down the tube to where the gametophyte(s) containing the female gametes are held within the carpel. After entering an ovum cell through the micropyle, one male nucleus fuses with the polar bodies to produce the endosperm tissues, while the other fuses with the ovule to produce the embr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allele
An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution. ::"The chromosomal or genomic location of a gene or any other genetic element is called a locus (plural: loci) and alternative DNA sequences at a locus are called alleles." The simplest alleles are single nucleotide polymorphisms (SNP). but they can also be insertions and deletions of up to several thousand base pairs. Popular definitions of 'allele' typically refer only to different alleles within genes. For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles (variants). In population genetics, nearly every living human's phenotype for the ABO gene is some combination of just these six alleles. Most alleles observed result in little or no change in the function of the gene product it codes for. However, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
