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Haloclava Producta
''Haloclava producta'' is a species of sea anemone in the family Haloclavidae, commonly known as the ghost anemone. This species is native to shallow water in the northwestern Atlantic Ocean, between Cape Hatteras and the Bay of Fundy, where it makes a temporary burrow in soft sediment. It is found on sand flats, both intertidally and subtidally. Description ''H. producta'' has an elongated column up to in length and an oral disc surrounded by a whorl of about twenty short, knobbed tentacles. The column has a very thin body wall and is studded with about twenty rows of hollow blisters; it makes up most of this anemone's surface area. At the base of the column, the pedal disc is modified into a "physa", an inflatable digging organ. Biology The water in the shallows where ''H. producta'' lives is sometimes low in oxygen. Under these conditions, the sea anemone extends its column and tentacles, perhaps to expose the largest possible area of epidermis to the water to increase oxygen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Stimpson
William Stimpson (February 14, 1832 – May 26, 1872) was a noted American scientist. He was interested particularly in marine biology. Stimpson became an important early contributor to the work of the Smithsonian Institution and later, director of the Chicago Academy of Sciences. Biography Stimpson was born in Boston, Massachusetts to Herbert Hathorne Stimpson and Mary Ann Devereau Brewer. The Stimpsons were of the colonial stock of Massachusetts, the earliest known member of the family being James Stimpson, who was married in 1661, in Milton. His mother died at an early age. William Stimpson's father was an ingenious inventor, and a leading merchant of Boston in the mid decades of the nineteenth century, trading as "H. & F. Stimpson, stoves and furnaces, corner of Congress and Water Streets. It was he who invented the "Stimpson range", the first sheet-iron cooking stove, famous in its day throughout New England. He also made improvements in rifles, and suggested the placin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Anemone
Sea anemones are a group of predation, predatory marine invertebrates of the order (biology), order Actiniaria. Because of their colourful appearance, they are named after the ''Anemone'', a terrestrial flowering plant. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and ''hydra (genus), Hydra''. Unlike jellyfish, sea anemones do not have a Jellyfish#Life history and behavior, medusa stage in their life cycle. A typical sea anemone is a single polyp (zoology), polyp attached to a hard surface by its base, but some species live in soft sediment, and a few float near the surface of the water. The polyp has a columnar trunk topped by an oral disc with a ring of tentacles and a central mouth. The tentacles can be retracted inside the body cavity or expanded to catch passing prey. They are armed with cnidocytes (stinging cells). In many species, additional n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haloclavidae
Haloclavidae is a family of sea anemones. Members of the family are found worldwide and many live largely buried in soft substrates with only their oral disc and tentacles protruding. Characteristics Members of this family mostly have elongated columns which are often differentiated into different regions. The column is either smooth or has tubercles or suckers on its surface. The base is often rounded and used for digging but in some species it is flattened and adhesive to small objects. There is usually no sphincter but when one is present, it is endodermal. The tentacles are short and there are seldom more than 48, arranged cyclically. The mesenteries or internal tissue walls are few. There are no muscles attaching them to the basal disc but they do have strong retractor muscles. At least six pairs of the mesenteries are perfect, reaching from the base as far as the actinopharynx or throat of the anemone. There is a single, well defined siphonoglyph The siphonoglyph is a ciliat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Hatteras
Cape Hatteras is a cape located at a pronounced bend in Hatteras Island, one of the barrier islands of North Carolina. Long stretches of beach, sand dunes, marshes, and maritime forests create a unique environment where wind and waves shape the topography. A large area of the Outer Banks is part of a National Park, called the Cape Hatteras National Seashore. It is also the nearest landmass on the North American mainland to Bermuda, which is about to the east-southeast. The treacherous waters off the coast of the Outer Banks are known as the Graveyard of the Atlantic, Over 600 ships wrecked here as victims of shallow shoals, storms, and war. Diamond Shoals, a bank of shifting sand ridges hidden beneath the turbulent sea off Cape Hatteras, has never promised safe passage for ships. In the past 400 years, the graveyard has claimed many lives, but island villagers saved many. As early as the 1870s, villagers served in the United States Life-Saving Service. Others staffed lightho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bay Of Fundy
The Bay of Fundy (french: Baie de Fundy) is a bay between the Canadian provinces of New Brunswick and Nova Scotia, with a small portion touching the U.S. state of Maine. It is an arm of the Gulf of Maine. Its extremely high tidal range is the highest in the world. The name is likely a corruption of the French word , meaning 'split'. Hydrology Tides The tidal range in the Bay of Fundy is about ; the average tidal range worldwide is only . Some tides are higher than others, depending on the position of the moon, the sun, and atmospheric conditions. Tides are semidiurnal, meaning they have two highs and two lows each day, with about six hours and 13 minutes between each high and low tide. Because of tidal resonance in the funnel-shaped bay, the tides that flow through the channel are very powerful. In one 12-hour tidal cycle, about 100 billion tons (110 billion short tons) of water flows in and out of the bay, which is twice as much as the combined total flow of all the rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peristalsis
Peristalsis ( , ) is a radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated contraction of involuntary circular muscles, which is preceded by a simultaneous contraction of the longitudinal muscle and relaxation of the circular muscle in the lining of the gut. In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus before being transformed into chyme in the stomach) along the tract. The peristaltic movement comprises relaxation of circular smooth muscles, then their contraction behind the chewed material to keep it from moving backward, then longitudinal contraction to push it forward. Earthworms use a similar mechanism to drive their locomotion, and some modern machinery imitate this design. The word comes from New Latin and is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (environmental)
Hypoxia refers to low oxygen conditions. Normally, 20.9% of the gas in the atmosphere is oxygen. The partial pressure of oxygen in the atmosphere is 20.9% of the total barometric pressure. In water, oxygen levels are much lower, approximately 7 ppm or 0.0007% in good quality water, and fluctuate locally depending on the presence of photosynthetic organisms and relative distance to the surface (if there is more oxygen in the air, it will diffuse across the partial pressure gradient). Atmospheric hypoxia Atmospheric hypoxia occurs naturally at high altitudes. Total atmospheric pressure decreases as altitude increases, causing a lower partial pressure of oxygen, which is defined as hypobaric hypoxia. Oxygen remains at 20.9% of the total gas mixture, differing from hypoxic hypoxia, where the percentage of oxygen in the air (or blood) is decreased. This is common in the sealed burrows of some subterranean animals, such as blesmols. Atmospheric hypoxia is also the basis of altitude tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Sulphide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The underground mine gas term for foul-smelling hydrogen sulfide-rich gas mixtures is ''stinkdamp''. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777. The British English spelling of this compound is hydrogen sulphide, a spelling no longer recommended by the Royal Society of Chemistry or the International Union of Pure and Applied Chemistry. Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or it or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death. Despite this, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatitis
Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to covering the entire body. Dermatitis is often called eczema, and the difference between those terms is not standardized. The exact cause of the condition is often unclear. Cases may involve a combination of allergy and poor venous return. The type of dermatitis is generally determined by the person's history and the location of the rash. For example, irritant dermatitis often occurs on the hands of those who frequently get them wet. Allergic contact dermatitis occurs upon exposure to an allergen, causing a hypersensitivity reaction in the skin. Prevention of atopic dermatitis is typically with essential fatty acids, and may be treated with moisturizers and steroid creams. The steroid creams should generally be of mid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Island
Long Island is a densely populated island in the southeastern region of the U.S. state of New York (state), New York, part of the New York metropolitan area. With over 8 million people, Long Island is the most populous island in the United States and the List of islands by population, 18th-most populous in the world. The island begins at New York Harbor approximately east of Manhattan Island and extends eastward about into the Atlantic Ocean and 23 miles wide at its most distant points. The island comprises four List of counties in New York, counties: Kings and Queens counties (the New York City Borough (New York City), boroughs of Brooklyn and Queens, respectively) and Nassau County, New York, Nassau County share the western third of the island, while Suffolk County, New York, Suffolk County occupies the eastern two thirds of the island. More than half of New York City's residents (58.4%) lived on Long Island as of 2020, in Brooklyn and in Queens. Culturally, many people in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York (state)
New York, officially the State of New York, is a state in the Northeastern United States. It is often called New York State to distinguish it from its largest city, New York City. With a total area of , New York is the 27th-largest U.S. state by area. With 20.2 million people, it is the fourth-most-populous state in the United States as of 2021, with approximately 44% living in New York City, including 25% of the state's population within Brooklyn and Queens, and another 15% on the remainder of Long Island, the most populous island in the United States. The state is bordered by New Jersey and Pennsylvania to the south, and Connecticut, Massachusetts, and Vermont to the east; it has a maritime border with Rhode Island, east of Long Island, as well as an international border with the Canadian provinces of Quebec to the north and Ontario to the northwest. New York City (NYC) is the most populous city in the United States, and around two-thirds of the state's popul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
