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Balsam Fir
''Abies balsamea'' or balsam fir is a North American fir, native to most of eastern and central Canada (Newfoundland west to central Alberta) and the northeastern United States (Minnesota east to Maine, and south in the Appalachian Mountains to West Virginia). Description Balsam fir is a small to medium-size evergreen tree typically tall, occasionally reaching a height of . The narrow conic crown consists of dense, dark-green leaves. The bark on young trees is smooth, grey, and with resin blisters (which tend to spray when ruptured), becoming rough and fissured or scaly on old trees. The leaves are flat and needle-like, long, dark green above often with a small patch of stomata near the tip, and two white stomatal bands below, and a slightly notched tip. They are arranged spirally on the shoot, but with the leaf bases twisted so that the leaves appear to be in two more-or-less horizontal rows on either side of the shoot. The needles become shorter and thicker the higher they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Linnaeus
Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern Taxonomy (biology), taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was the son of a curate and was born in Råshult, in the countryside of Småland, southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microspore
Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote. Megaspores are structures that are part of the alternation of generations in many seedless vascular cryptogams, all gymnosperms and all angiosperms. Plants with heterospory, heterosporous life cycles using microspores and megaspores arose independently in several plant groups during the Devonian period. Microspores are haploid, and are produced from diploid microsporocytes by meiosis. Morphology The microspore has three different types of wall layers. The outer layer is called the perispore, the next is the exospore, and the inner layer is the endospore. The perispore is the thickest of the three layers while the exospore and endospore are relatively equal in width. Seedless vascular plants In heterosporous seedless vascular plants, modified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picea Rubens
''Picea rubens'', commonly known as red spruce, is a species of spruce native to eastern North America, ranging from eastern Quebec and Nova Scotia, west to the Adirondack Mountains and south through New England along the Appalachians to western North Carolina and eastern Tennessee.Farjon, A. (1990). ''Pinaceae. Drawings and Descriptions of the Genera''. Koeltz Scientific Books . This species is also known as yellow spruce, West Virginia spruce, eastern spruce, and he-balsam. Red spruce is the provincial tree of Nova Scotia. Description Red spruce is a perennial, shade-tolerant, late successional coniferous tree that under optimal conditions grows to tall with a trunk diameter of about , though exceptional specimens can reach tall and in diameter. It has a narrow conical crown. The leaves are needle-like, yellow-green, long, four-sided, curved, with a sharp point, and extend from all sides of the twig. The bark is gray-brown on the surface and red-brown on the inside, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphagnum
''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store water, since both living and dead plants can hold large quantities of water inside their cells; plants may hold 16 to 26 times as much water as their dry weight, depending on the species.Bold, H. C. 1967. Morphology of Plants. second ed. Harper and Row, New York. p. 225–229. The empty cells help retain water in drier conditions. As ''Sphagnum'' moss grows, it can slowly spread into drier conditions, forming larger mires, both raised bogs and blanket bogs. Thus, ''Sphagnum'' can influence the composition of such habitats, with some describing ''Sphagnum'' as 'habitat manipulators' or 'autogenic ecosystem engineers'. These peat accumulations then provide habitat for a wide array of peatland plants, including sedges and Calcifuge, ericaceous shrubs, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swamp
A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in creating this environment. Swamps vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water, or seawater. Freshwater swamps form along large rivers or lakes where they are critically dependent upon rainwater and seasonal flooding to maintain natural water level fluctuations.Hughes, F.M.R. (ed.). 2003. The Flooded Forest: Guidance for policy makers and river managers in Europe on the restoration of floodplain forests. FLOBAR2, Department of Geography, University of Cambridge, Cambridge, UK. 96 p. Saltwater swamps are found along tropical and subtropical coastlines. Some swamps have hammock (ecology), hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carter Dome Seen From Mt Hight
Carter(s), or Carter's, Tha Carter, or The Carter(s), may refer to: Geography United States * Carter, Arkansas, an unincorporated community * Carter, Mississippi, an unincorporated community * Carter, Montana, a census-designated place * Carter, Oklahoma, a town * Carter, South Dakota, an unincorporated community * Carter, Texas, a census-designated place * Carter, Forest County, Wisconsin, an unincorporated community * Carter, Iron County, Wisconsin, an unincorporated community * Carter, Wyoming, a census-designated place * Carters, Georgia, an unincorporated community * Carter County (other) * Carter Township (other) Canada * Carter Islands, Nunavut, Canada People and fictional characters * Carter (name), a surname and a given name, including a list of people and fictional characters * Carter, someone whose occupation is transporting goods by cart or wagon Arts and entertainment Music Groups * Carter the Unstoppable Sex Machine, an English indie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fraser Fir
The Fraser fir (''Abies fraseri''), sometimes spelled Frasier fir, is an endangered species of fir native to the Appalachian Mountains of the southeastern United States. They are endemic to only seven montane regions in the Appalachian Mountains. Taxonomy ''Abies fraseri'' is closely related to ''Abies balsamea'' (balsam fir), of which it has occasionally been treated as a subspecies (as ''A. balsamea'' subsp. ''fraseri'' (Pursh) E.Murray) or a variety (as ''A. balsamea'' var. ''fraseri'' (Pursh) Spach).Farjon, A. (1990). ''Pinaceae. Drawings and Descriptions of the Genera''. Koeltz Scientific Books .Liu, T.-S. (1971). ''A Monograph of the Genus Abies''. National Taiwan University.Flora of North America''Abies fraseri''/ref>Gymnosperm Database''Abies fraseri''/ref> Some botanists regard the variety of balsam fir named ''Abies balsamea'' var. ''phanerolepis'' as a natural hybrid with Fraser fir, denominated ''Abies × phanerolepis'' (Fernald) Liu. Names The species ''Abies fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canaan Valley, West Virginia
Canaan Valley () is a large bathtub-shaped upland valley in northeastern Tucker County, West Virginia, USA. Within it are extensive wetlands and the headwaters of the Blackwater River which spills out of the valley at Blackwater Falls. It is a well-known and partially undeveloped scenic attraction and tourist draw. Since 1994, almost 70% of the Valley has become the Canaan Valley National Wildlife Refuge, the nation's 500th National Wildlife Refuge, with Canaan Valley Resort State Park and Blackwater Falls State Park nearby. Canaan Valley was designated a National Natural Landmark in 1974. The National Park Service citation indicates that the Valley is "a splendid 'museum' of Pleistocene habitats ... contain ng... an aggregation of these habitats seldom found in the eastern United States. It is unique as a northern boreal relict community at this latitude by virtue of its size, elevation and diversity." The local pronunciation of "Canaan" is , rather than the conventional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quebec
Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, New Brunswick to the southeast and a coastal border with the territory of Nunavut. In the south, it shares a border with the United States. Between 1534 and 1763, what is now Quebec was the List of French possessions and colonies, French colony of ''Canada (New France), Canada'' and was the most developed colony in New France. Following the Seven Years' War, ''Canada'' became a Territorial evolution of the British Empire#List of territories that were once a part of the British Empire, British colony, first as the Province of Quebec (1763–1791), Province of Quebec (1763–1791), then Lower Canada (1791–1841), and lastly part of the Province of Canada (1841–1867) as a result of the Lower Canada Rebellion. It was Canadian Confederation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilisation
Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a zygote and initiate its development into a new individual organism or offspring. While processes such as insemination or pollination, which happen before the fusion of gametes, are also sometimes informally referred to as fertilisation, these are technically separate processes. The cycle of fertilisation and development of new individuals is called sexual reproduction. During double fertilisation in angiosperms, the haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. History In antiquity, Aristotle conceived the formation of new individuals through fusion of male and female fluids, with form and function emerging gradually, in a mode called by him as epigenetic. In 1784, Spallanzani established the need of in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen Tube
A pollen tube is a tubular structure produced by the male gametophyte of seed plants when it germinates. Pollen tube elongation is an integral stage in the plant life cycle. The pollen tube acts as a conduit to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms. In maize, this single cell can grow longer than to traverse the length of the pistil. Pollen tubes were first discovered by Giovanni Battista Amici in the 19th century. They are used as a model for understanding plant cell behavior. Research is ongoing to comprehend how the pollen tube responds to extracellular guidance signals to achieve fertilization. Pollen tubes are unique to seed plants and their structures have evolved over their history since the Carboniferous period. Pollen tube formation is complex and the mechanism is not fully understood. Angiosperms The male ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
