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Edwardsiella Lineata
''Edwardsiella lineata'', the lined anemone, is a species of sea anemone in the family Edwardsiidae. It is native to the northwestern Atlantic Ocean where it occurs in the subtidal zone. Description ''E. lineata'' is a small, delicate-looking, white or brownish anemone with a typical length of 15-20 millimeters as an adult polyp. It has a simple body plan, possessing only 8 complete mesenteries, and 18-24 tentacles. The body of an adult is composed of four distinct regions defined by tissue type: the oral disc containing the tentacles, the capitulum which houses the actinopharynx or "gut", the scapus, and the aboral end. It is capable of lengthening and shortening its body using retractor and parietal muscles present on these mesenteries. It possesses various types of cnidae, including acontia (threadlike defensive organs thrown out of the mouth or special pores when irritated). It lives in a slender mucous tube immersed in sediment. Distribution and habitat ''E. lineata'' is nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addison Emery Verrill
Addison Emery Verrill (February 9, 1839 – December 10, 1926) was an American invertebrate zoologist, museum curator and university professor. Life Verrill was born on February 9, 1839 in Greenwood, Maine, the son of George Washington Verrill and Lucy (Hillborn) Verrill. As a boy he showed an early interest in natural history, building collections of rocks and minerals, plants, shells, insects and other animals. When he moved with his family to Norway, Maine at age fourteen he attended secondary school at the Norway Liberal Institute. Verrill started college in 1859 at Harvard University and studied under Louis Agassiz. He graduated in 1862 with a B.A. He went on scientific collecting trips with Alpheus Hyatt and Nathaniel Shaler in the summer of 1860 to Trenton Point, Maine and Mount Desert Island and in the summer of 1861 to Anticosti Island and Labrador. In 1864 Verrill made reports on mining, or prospective mining, properties in New Hampshire, New York, and Pennsylvania. Tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seabather's Eruption
Seabather's eruption is an itching dermatitis caused by a hypersensitivity reaction to the immature nematocysts of larval-stage thimble jellyfish (''Linuche unguiculata''), sea anemones (''Edwardsiella lineata'') and other larval cnidarians. The cause is sometimes attributed to "sea lice" or "sea ants", but sea lice (Caligidae) are crustacean parasites of fish only. It should not be confused with swimmer's itch. Symptoms and signs Symptoms generally arise later after one takes a shower. It is unusual to notice the eruptions immediately. Symptoms can last from a few days up to two weeks, the shorter time being the norm. The reaction is identified by severe itching around small red papules 1mm to 1.5 cm in size located on areas of skin that were covered by water-permeable clothing or hair during ocean swimming. Initial swimmer exposure to the free-floating larvae produces no effects, as each organism possesses only a single undeveloped nematocyst which is inactive while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, fish, amphibians, mollusks, crustaceans, cnidarians, echinoderms, and tunicates undergo metamorphosis, which is often accompanied by a change of nutrition source or behavior. Animals can be divided into species that undergo complete metamorphosis (" holometaboly"), incomplete metamorphosis ("hemimetaboly"), or no metamorphosis (" ametaboly"). Scientific usage of the term is technically precise, and it is not applied to general aspects of cell growth, including rapid growth spurts. Generally organisms with a larva stage undergo metamorphosis, and during metamorphosis the organism loses larval characteristics. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mnemiopsis
''Mnemiopsis leidyi'', the warty comb jelly or sea walnut, is a species of tentaculate ctenophore (comb jelly). It is native to western Atlantic coastal waters, but has become established as an invasive species in European and western Asian regions. Three species have been named in the genus ''Mnemiopsis'', but they are now believed to be different ecological forms of a single species ''M. leidyi'' by most zoologists. Description and ecology ''Mnemiopsis'' have an oval-shaped and transparent lobed body, with four rows of ciliated combs that run along the body vertically and glow blue-green when disturbed. They have several feeding tentacles. Unlike cnidarians, ''Mnemiopsis'' does not sting. Their body comprises 97% water. They have a maximum body length of roughly and a diameter of . It is euryoecious, tolerating a wide range of salinity (2 to 38 psu), temperature (), and water quality. ''Mnemiopsis'' is a carnivore that consumes zooplankton including crustaceans, other com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenophora
Ctenophora (; ctenophore ; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are the largest animals to swim with the help of cilia. Depending on the species, adult ctenophores range from a few millimeters to in size. Only 100 to 150 species have been validated, and possibly another 25 have not been fully described and named. The textbook examples are cydippids with egg-shaped bodies and a pair of retractable tentacles fringed with tentilla ("little tentacles") that are covered with colloblasts, sticky cells that capture prey. Their bodies consist of a mass of jelly, with a layer two cells thick on the outside, and another lining the internal cavity. The phylum has a wide range of body forms, including the egg-shaped cydippids with retractable tentacles that capture prey, the flat generally combless plat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematostella Vectensis
The starlet sea anemone (''Nematostella vectensis'') is a species of small sea anemone in the family Edwardsiidae native to the east coast of the United States, with introduced populations along the coast of southeast England and the west coast of the United States (class ''Anthozoa'', phylum ''Cnidaria'', a sister group of Bilateria). Populations have also been located in Nova Scotia, Canada. This sea anemone is found in the shallow brackish water of coastal lagoons and salt marshes where its slender column is usually buried in the mud and its tentacles exposed. Its genome has been sequenced and it is cultivated in the laboratory as a model organism, but the IUCN has listed it as being a "Vulnerable species" in the wild. Description The starlet sea anemone has a bulbous basal end and a contracting column that ranges in length from less than . There is a fairly distinct division between the scapus, the main part of the column, and the capitulum, the part just below the crown of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematocyst
A cnidocyte (also known as a cnidoblast or nematocyte) is an explosive cell containing one large secretory organelle called a cnidocyst (also known as a cnida () or nematocyst) that can deliver a sting to other organisms. The presence of this cell defines the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). Cnidae are used to capture prey and as a defense against predators. A cnidocyte fires a structure that contains a toxin within the cnidocyst; this is responsible for the stings delivered by a cnidarian. Structure and function Each cnidocyte contains an organelle called a cnida, cnidocyst, nematocyst, ptychocyst or spirocyst. This organelle consists of a bulb-shaped capsule containing a coiled hollow tubule structure attached to it. An immature cnidocyte is referred to as a cnidoblast or nematoblast. The externally oriented side of the cell has a hair-like trigger called a cnidocil, which is a mechano- and chemo-receptor. When the trigger is activated, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venom
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a stinger, in a process called envenomation. Venom is often distinguished from poison, which is a toxin that is passively delivered by being ingested, inhaled, or absorbed through the skin, and toxungen, which is actively transferred to the external surface of another animal via a physical delivery mechanism. Venom has evolved in terrestrial and marine environments and in a wide variety of animals: both predators and prey, and both vertebrates and invertebrates. Venoms kill through the action of at least four major classes of toxin, namely necrotoxins and cytotoxins, which kill cells; neurotoxins, which affect nervous systems; myotoxins, which damage muscles; and haemotoxins, which disrupt blood clotting. Venomous animals cause tens of thousa ... [...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] |
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] |
Parasitism
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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