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Pisaster Brevispinus
''Pisaster brevispinus'', commonly called the pink sea star, giant pink sea star, or short-spined sea star, is a species of sea star in the northeast Pacific Ocean. It was first described to science by William Stimson in 1857. The type specimen was collected on a sandy bottom, deep, near the mouth of San Francisco Bay. Description The pink sea star has five thick arms and a large central disc. It is one of the largest sea stars in the world. While typically having a diameter of , monsters up to have been found. The largest animals may weigh . The upper, arboral, surface of this star is generally pink, sometimes with shadings of gray. The radius of the arms is 2.8 to 5.0 times the radius of the central disc. The central disc contains an obvious madreporite on its upper surface. This structure filters water used by the animal. The mouth of the animal is found on the underside of the central disc. There are short, spines on the upper surface of the star. While a ... [...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] |
Zygote
A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicellular organisms, the zygote is the earliest developmental stage. In humans and most other anisogamous organisms, a zygote is formed when an egg cell and sperm cell come together to create a new unique organism. In single-celled organisms, the zygote can divide asexually by mitosis to produce identical offspring. German zoologists Oscar and Richard Hertwig made some of the first discoveries on animal zygote formation in the late 19th century. Humans In human fertilization, a released ovum (a haploid secondary oocyte with replicate chromosome copies) and a haploid sperm cell (male gamete) combine to form a single diploid cell called the zygote. Once the single sperm fuses with the oocyte, the latter completes the division of the second ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tresus Capax
''Tresus capax'' is a species of saltwater clam, marine bivalve mollusk, common name the fat gaper, in the family Mactridae. It also shares the common name horse clam with '' Tresus nuttallii'' a species which is similar in morphology and lifestyle. Both species are somewhat similar to the geoduck (''Panopea generosa'', which is in the family Hiatellidae), though smaller, with shells up to eight inches long (20 cm), weight to 3–4 lb (1.4–1.8 kg). The two species commonly known as horse clams inhabit the Pacific coast intertidal zones: the pacific gaper, ''T. nuttallii'', more abundant south to California; and the fat gaper, ''T. capax'', more abundant north to Alaska. Both have oval and chalky-white or yellow shells with patches of brown periostracum (leather-like skin) on the shell. These clams are also commonly called gapers because their shells are flared around the siphon and do not completely close, rather like geoduck clams. Like geoducks, they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solen Sicarius
Solen may refer to: * Solen, Ancient Greek name for the Thamirabarani River * Solen, North Dakota * ''Solen'' (bivalve), a genus of molluscs in family Solenidae * ''Solen'' (ship), a Swedish galleon * Solen Désert-Mariller Solen Désert-Mariller (born 2 August 1982) is a French sprinter who specializes in the 400 metres. She was born in Brest. She competed in the 200 metres at the 2003 World Indoor Championships, and then in the 400 metres at the 2003 World Champi ... (born 1982), French sprinter See also * Sølen, mountain in Norway {{disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saxidomus Gigantea
''Saxidomus gigantea'' is a large, edible saltwater clam, a marine bivalve mollusk in the family Veneridae, the venus clams. It can be found along the western coast of North America, ranging from the Aleutian Islands to San Francisco Bay. Common names for this clam include butter clam, Washington clam, smooth Washington clam and money shell. Numerous valves of this species have been found in the shell middens on Sidney Island in British Columbia, Canada. Description This large clam can live for more than twenty years and grow to a length of , with smaller individuals being nearly as high as they are long. The umbones are set at an angle of more than 110° and the ligament joining the valves is black and external. There are no radial ridges but the oval valves are sculpted by well-defined concentric rings. Each valve has three cardinal teeth. The general color of the exterior of the shell is white, but this may be stained reddish-brown by iron sulfide from the sediment. The inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clinocardium Nuttallii
''Clinocardium '' is a genus of marine bivalve molluscs in the family Cardiidae, the cockles. It is monotypic, being represented by the single species ''Clinocardium nuttallii'', also known as the basket cockle or Nuttall's cockle, a large edible saltwater clam. Native to the coastlines of California and the Pacific Northwest, this species can be found from the Bering Sea to Southern California and has been used by the indigenous peoples of California and the Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Tho ... as food. References * Biodiversity of the Central Coast entr* WoRMS entr Cardiidae Bivalve genera Fauna of California Seafood in Native American cuisine Bivalves described in 1837 {{bivalve-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cockle (bivalve)
A cockle is an edible marine bivalve mollusc. Although many small edible bivalves are loosely called cockles, true cockles are species in the family Cardiidae. MolluscaBase eds. (2022). MolluscaBase. Cardiidae Lamarck, 1809. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=229 on 2022-02-09 True cockles live in sandy, sheltered beaches throughout the world. The distinctive rounded shells are bilaterally symmetrical, and are heart-shaped when viewed from the end. Numerous radial, evenly spaced ribs are a feature of the shell in most but not all genera (for an exception, see the genus ''Laevicardium'', the egg cockles, which have very smooth shells). The shell of a cockle is able to close completely (i.e., there is no "gap" at any point around the edge). Though the shell of a cockle may superficially resemble that of a scallop because of the ribs, cockles can be distinguished from scallops morphologically in that co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalvia
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estim ... that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, Cockle (bivalve), cockles, mussels, scallops, and numerous other family (biology), families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into Ctenidium (mollusc), ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primordium
A primordium (; plural: primordia; synonym: anlage) in embryology, is an organ or tissue in its earliest recognizable stage of development. Cells of the primordium are called primordial cells. A primordium is the simplest set of cells capable of triggering growth of the would-be organ and the initial foundation from which an organ is able to grow. In flowering plants, a floral primordium gives rise to a flower. Although it is a frequently used term in plant biology, the word is used in describing the biology of all multicellular organisms (for example: a tooth primordium in animals, a leaf primordium in plants or a sporophore primordium in fungi.) Primordium development in plants Plants produce both leaf and flower primordia cells at the shoot apical meristem (SAM). Primordium development in plants is critical to the proper positioning and development of plant organs and cells. The process of primordium development is intricately regulated by a set of genes that affect the pos ... [...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 bilateral symmetry, unlike the adult starfish, which have a pentaradial symmetry. Starfish of the order Paxillosida (''Astropecten'' and '' 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 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 the adult grow, with the larval arms eventually degenerating and disappearing. The digestive system of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipinnaria
A bipinnaria is the first stage in the larval development of most starfish, and is usually followed by a brachiolaria stage. Movement and feeding is accomplished by the bands of cilia. Starfish that brood their young generally lack a bipinnaria stage, with the eggs developing directly into miniature adults The bipinnaria is free-living, swimming as part of the zooplankton. When it initially forms, the entire body is covered by cilia, but as it grows, these become confined to a narrow band forming a number of loops over the body surface. A pair of short, stubby arms soon develop on the body, with the ciliated bands extending into them. In addition to propelling the larva through the water, the cilia also catch suspended food particles, and deliver them to the mouth (more correctly called a ''stomodeum''). Eventually, three additional arms develop at the front end of the larva; at this point it becomes a brachiolaria. In some species, including the common starfish ''Asterias'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrula
Gastrulation is the stage in the early embryonic development of most animals, during which the blastula (a single-layered hollow sphere of Cell (biology), cells), or in mammals the blastocyst is reorganized into a multilayered structure known as the gastrula. Before gastrulation, the embryo is a continuous Epithelium, epithelial sheet of cells; by the end of gastrulation, the embryo has begun Cellular differentiation, differentiation to establish distinct cell lineages, set up the basic axes of the body (e.g. Anatomical terms of location#Dorsal and ventral, dorsal-ventral, Anatomical terms of location#Anterior and posterior, anterior-posterior), and internalized one or more cell types including the prospective Gastrointestinal tract, gut. In Triploblasty, triploblastic organisms, the gastrula is trilaminar (three-layered). These three germ layers are the ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer).Mundlos 2009p. 422/ref>McGeady, 2004: p. 34 In Diplo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
