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Echinaster Echinophorus
The orange knobby star, ''Echinaster echinophorus'', is a species of sea star found in the Caribbean Sea and along the Atlantic coast of South America. Description It is a small species with a diameter of up to . It has a small central disc and five spatulate arms, tapering very little and with rounded tips. The arms are oval in cross section and on the aboral (upper) side have one or two rows of bluntly conical spines, and more rows of spines on the sides of the arms and on the oral (under) surface, on either side of the ambulacral grooves. The colour is usually some shade of red or orange. Distribution and habitat ''Echinaster echinophorus'' is found in shallow water in Florida, the Caribbean Sea, the Bahamas, Venezuela, and northern Brazil at depths ranging from and at a sea temperature of about 27 °C (8 °F). It occurs on reefs, rocks, and areas of coral rubble and sometimes among mangroves. Biology In Florida, ''Echinaster echinophorus'' spawns in late spring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Baptiste Lamarck
Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (; ), was a French naturalist, biologist, academic, and soldier. He was an early proponent of the idea that biological evolution occurred and proceeded in accordance with Naturalism (philosophy), natural laws. Lamarck fought in the Seven Years' War against Prussia, and was awarded a commission for bravery on the battlefield. Posted to Monaco, Lamarck became interested in natural history and resolved to study medicine.#Packard, Packard (1901), p. 15. He retired from the army after being injured in 1766, and returned to his medical studies. Lamarck developed a particular interest in botany, and later, after he published the three-volume work ''Flore françoise'' (1778), he gained membership of the French Academy of Sciences in 1779. Lamarck became involved in the Jardin des Plantes and was appointed to the Chair of Botany in 1788. When the French Nationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish, and baleen whales. Marine plankton include bacteria, archaea, algae, protozoa, microscopic fungi, and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. fresh water, Freshwater plankton are similar to marine plankton, but are found in lakes and rivers. Mostly, plankton just drift where currents take them, though some, like jellyfish, swim slowly but not fast enough to generally overcome the influence of currents. Although plankton are usually thought of as inhabiting water, there are also airborne versions that live part of their lives drifting in the at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinaster
''Echinaster'' is a well-studied and common genus of starfish containing ~30 species and is the second-largest genus found within the family Echinasteridae. The genera ''Henricia'' and ''Echinaster'' encompass 90% of all the species found within the family Echinasteridae. It contains 30 species, however the number of species in this genus is still debatable because of uncertainty within the genera. This genus is currently sub-divided into two sub-genera: ''Echinaster'' and ''Othilia'', evolutionary relationships between the sub-genera is not understood. ''Echinaster'' are found in the Pacific, Atlantic and Indian oceans, with most species being studied in the Gulf of Mexico and Brazil. The sub-genera ''Othilia'' is thought to encompass species mainly found in the Gulf of Mexico and Brazil. ''Echinaster'' is often one of the most studied species within the family Echinasteridae and is often used to find evolutionary relationships. Many species found within ''Echinaster'' are red, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliclona Compressa
''Amphimedon compressa'', the erect rope sponge, red tree sponge, red tubular sponge, or red sponge is a demosponge found in southern Florida, the Caribbean Sea, and the Bahamas. It can be deep red, orange, brown, or black. Taxonomy The erect rope sponge used to be classified as ''Haliclona rubens'', but this was determined to be a synonym of ''Haliclona compressa''. This name, however, is no longer accepted, and the World Porifera Database lists this species as ''Amphimedon compressa'' – Duchassaing & Michelotti, 1864. Description ''Amphimedon compressa'' can grow to a length of and a diameter of , but it is usually smaller in shallow water. The tree-like curved branches grow from a basal encrusting mass, but very occasionally this sponge grows as a small, unbranched, flattened hemisphere. Many small osculi are found on the branches. It is usually a dull dark red, but the colour varies and it is sometimes black, dark brown, greyish-brown, bright red, or orange. In dark posi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutaneous Leishmaniasis
Cutaneous leishmaniasis is the most common form of leishmaniasis affecting humans. It is a skin infection caused by a Trypanosomatid, single-celled parasite that is Vector (epidemiology), transmitted by the bite of a Phlebotominae, phlebotomine sand fly. About 30 species of ''Leishmania'' may cause skin, cutaneous leishmaniasis. This disease is considered to be a zoonosis (an infectious disease that is naturally transmissible from animals to humans), with the exception of ''Leishmania tropica'', which is often an anthroponotic disease (an infectious disease that is naturally transmissible from humans to vertebrate animals). Signs and symptoms Post kala-azar dermal leishmaniasis Post-kala-azar dermal leishmaniasis (PKDL) is a recurrence of Visceral leishmaniasis, ''kala-azar'' that may appear on the skin of affected individuals months and up to 20 years after being partially treated, untreated, or even in those considered adequately treated. In Sudan, they can be demonstrated in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) 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 characterised parasites' way of feeding 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), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protozoa
Protozoa (: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans were regarded as "one-celled animals". When first introduced by Georg Goldfuss, in 1818, the taxon Protozoa was erected as a class within the Animalia, with the word 'protozoa' meaning "first animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae. This classification remained widespread in the 19th and early 20th century, and even became elevated to a variety of higher ranks, including phylum, subkingdom, kingdom, and then sometimes included within the paraphyletic Protoctista or Protista. By the 1970s, it became usual to require that all taxa be monophyletic (derived from a common ancestor that would also be regarded as protozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leishmania
''Leishmania'' () is a genus of parasitic protozoans, single-celled eukaryotic organisms of the trypanosomatid group that are responsible for the disease leishmaniasis. The parasites are transmitted by sandflies of the genus '' Phlebotomus'' in the Old World, and of the genus '' Lutzomyia'' in the New World. There are 53 species and about 20 of them are responsible for human infections. They are transmitted by around 100 species of sandflies. The primary hosts are vertebrates. They commonly infect hyraxes, canids, rodents, and humans. History Members of an ancient genus of ''Leishmania''-like parasites, '' Paleoleishmania'', have been detected in fossilized sand flies dating back to the early Cretaceous period. The first written reference to the conspicuous symptoms of cutaneous leishmaniasis surfaced in the Paleotropics within oriental texts dating back to the 7th century BC (allegedly transcribed from sources several hundred years older, between 1500 and 2000 BC). D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Activity
In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore but can be modified by the other constituents. Among the various properties of chemical compounds, pharmacological/biological activity plays a crucial role since it suggests uses of the compounds in the medical applications. However, chemical compounds may show some adverse and toxic effects which may prevent their use in medical practice. Biological activity is usually measured by a bioassay and the activity is generally dosage-dependent, which is investigated via dose-response curves. Further, it is common to have effects ranging from beneficial to adverse for one substance when going from low to high doses. Activity depends critically on fulfillment of the ADME criteria. To be an effective drug, a compound not only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolite
Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved in the normal cell growth, growth, Biological development, development, or reproduction of the organism. Instead, they generally mediate ecological biological interaction, interactions, which may produce a Natural selection, selective advantage for the organism by increasing its survivability or fecundity. Specific secondary metabolites are often restricted to a narrow set of species within a phylogenetic group. Secondary metabolites often play an important role in plant defense against herbivory and other interspecies defenses. Humans use secondary metabolites as medicines, flavourings, pigments, and recreational drugs. The term secondary metabolite was first coined by Albrecht Kossel, the 1910 Nobel Prize laureate for medicine and physio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachiolaria
A brachiolaria is the second stage of larval development in many starfishes. It follows the bipinnaria. Brachiolaria have symmetry (biology)#Bilateral_symmetry, bilateral symmetry, unlike the adult starfish, which have a symmetry (biology)#Pentamerism, pentaradial symmetry. Starfish of the order Paxillosida (''Astropecten'' and ''Asterina (starfish), Asterina'') have no brachiolaria stage, with the bipinnaria developing directly into an adult. The brachiolaria develops from the bipinnaria larva when the latter grows three short arms at the underside of its anterior end. These arms each bear sticky cells at the tip, and they surround an adhesive sucker. The larva soon sinks to the bottom, attaching itself to the substrate, firstly with the tips of the arms, and then with the sucker. Once attached, it begins to metamorphosis, metamorphose into the adult form. The adult starfish develops only from the hind-part of the larva, away from the sucker. It is from this part that the arms of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spawn (biology)
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is known as spawning. The vast majority of aquatic and amphibious animals reproduce through spawning. These include the following groups: * Bony fishes * Crustaceans (such as crabs, shrimps, etc.) *Mollusks (such as oysters, octopus, squid) *Echinoderms (such as sea urchins, sea stars, sea cucumbers, etc.) * Amphibians (such as frogs, toads, salamanders, newts) * Aquatic insects (such as dragonflies, mayflies, mosquitoes) *Coral, which are living colonies of tiny, aquatic organisms—not plants, as they are sometimes perceived to be. Corals, while appearing sedentary or botanical by nature, actually spawn by releasing clouds of sperm and egg cells into the water column, where the two mix. As a general rule, aquatic or semiaquatic reptiles, birds, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
