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Sphaerosyllis Voluntariorum
''Sphaerosyllis voluntariorum'' is a species belonging to the phylum Annelida, a group known as the segmented worms.San Martín, G. (2005). Exogoninae (Polychaeta: Syllidae) from Australia with the description of a new genus and twenty-two new species. Records of the Australian Museum. 57(1): 39-152., available online at https://dx.doi.org/10.3853/j.0067-1975.57.2005.1438, page(s): 55-57, figs. 11A-G, 12A-E. This species is closely related to '' Sphaerosyllis bifurcata'', '' Sphaerosyllis bifurcatoides'' and '' Sphaerosyllis rotundipapillata'', all endemic species to Australia, characterized by having large dorsal papillae, sometimes trilobed, and with shafts of compound chaetae distally bifid. ''S. voluntariorum'' is more densely papillated on its anterior segments and has a long subdistal spine on the ventral simple chaetae. This species' name alludes to the volunteers of the Marine Invertebrate section of The Australian Museum, who sorted specimens of syllids that led to the des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annelida
The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The annelids are Symmetry in biology, bilaterally symmetrical, Triploblasty, triploblastic, coelomate, invertebrate organisms. They also have Parapodium, parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistics, Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Siboglinidae, Pogonophora, Echiura and Sipuncula, previ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI Unit, SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cell (biology), cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular microalgae, such as cyanobacteria, ''Chlorella'', and diatoms, to multicellular macroalgae such as kelp or brown algae which may grow up to in length. Most algae are aquatic organisms and lack many of the distinct cell and tissue types, such as stomata, xylem, and phloem that are found in embryophyte, land plants. The largest and most complex marine algae are called seaweeds. In contrast, the most complex freshwater forms are the Charophyta, a Division (taxonomy), division of green algae which includes, for example, ''Spirogyra'' and stoneworts. Algae that are carried passively by water are plankton, specifically phytoplankton. Algae constitute a Polyphyly, polyphyletic group because they do not include a common ancestor, and although Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Australia
Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Australia is Australia's largest state, with a land area of , and is also the List of country subdivisions by area, second-largest subdivision of any country on Earth. Western Australia has a diverse range of climates, including tropical conditions in the Kimberley (Western Australia), Kimberley, deserts in the interior (including the Great Sandy Desert, Little Sandy Desert, Gibson Desert, and Great Victoria Desert) and a Mediterranean climate on the south-west and southern coastal areas. the state has 2.965 million inhabitants—10.9 percent of the national total. Over 90 percent of the state's population live in the South-West Land Division, south-west corner and around 80 percent live in the state capital Perth, leaving the remainder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Range National Park
Cape Range National Park is a national park in the Gascoyne region of Western Australia, north of Perth. The park occupies the western side of the North West Cape peninsula over an area of . The nearest town is Exmouth, and directly off the coast is the Ningaloo Reef. The area resulted from a gradual uplifting from the sea floor followed by fluctuating sea levels, wind and water erosion that have slowly eroded the range and plain leaving behind a range of rugged limestone, deep canyons, and pristine beaches. There is also an eponymous locality of the Shire of Exmouth, but the boundaries of the national park and the locality are not identical. Overview The Cape is the only elevated plateau composed of limestone on the North West Coast. The range has plateaus to an elevation of and forms the backbone of the peninsula which extends as far as North West Cape. Yardie Creek, a spectacular gorge where the water is trapped by a sandbar, is located within the park. Over 700 ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papilla
Papilla (Latin, 'nipple') or papillae may refer to: In animals * Papilla (fish anatomy), in the mouth of fish * Papilla (worms), small bumps on the surface of certain worms * Basilar papilla, a sensory organ of lizards, amphibians and fish * Dental papilla, in a developing tooth * Dermal papillae, part of the skin structure * Major duodenal papilla, in the duodenum * Minor duodenal papilla, in the duodenum * Genital papilla, a feature of the external genitalia of some animals * Mammary papilla or nipple, a raised region of tissue on the surface of the breast * Interdental papilla, part of the gums * Lacrimal papilla, on the bottom eyelid * Lingual papillae, small structures on the upper surface of the tongue * Renal papilla, part of the kidney * Tumor papilla, consisting of tumor cells surrounding a fibrovascular core In plants and fungi * Papilla (mycology), a nipple-shaped protrusion in the center of the cap * Stigmatic papilla, part of the stigma (botany) See also * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygidium
The pygidium (: pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is composed of fused body segments, sometimes with a tail, and separated from thoracic segments by an articulation.Shultz, J.W. (1990). Evolutionary Morphology And Phylogeny of Arachnida. Cladistics 6: 1–38. Chelicerates In arachnids, the pygidium is formed by reduction of the last three opisthosomal segments to rings where there is no distinction between tergites and sternites. A pygidium is present in Palpigradi, Amblypygi, Uropygi, Schizomida, Ricinulei and in the extinct order Trigonotarbida. It is also present in early fossil representatives of horseshoe crabs. Trilobites In trilobites, the pygidium can range from extremely small (much smaller than the head, or cephalon) to larger than the cephalon. They can be smooth, as in order ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Cell
A muscle cell, also known as a myocyte, is a mature contractile Cell (biology), cell in the muscle of an animal. In humans and other vertebrates there are three types: skeletal muscle, skeletal, smooth muscle, smooth, and Cardiac muscle, cardiac (cardiomyocytes). A skeletal muscle cell is long and threadlike with multinucleated, many nuclei and is called a ''muscle fiber''. Muscle cells develop from embryonic precursor cells called myoblasts. Skeletal muscle cells form by cell fusion, fusion of myoblasts to produce multinucleated cells (syncytium, syncytia) in a process known as myogenesis. Skeletal muscle cells and cardiac muscle cells both contain myofibrils and sarcomeres and form a striated muscle tissue. Cardiac muscle cells form the cardiac muscle in the walls of the heart chambers, and have a single central Cell nucleus, nucleus. Cardiac muscle cells are joined to neighboring cells by intercalated discs, and when joined in a visible unit they are described as a ''cardiac m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proventriculus
The proventriculus is part of the digestive system of birds.Encarta World English Dictionary orth American Edition(2007). ''Proventriculus''. Source: (accessed: December 18, 2007) An analogous organ exists in invertebrates and insects. Birds The proventriculus is a standard part of avian anatomy and is a rod-shaped organ, located between the esophagus and the gizzard of most birds. It is generally a glandular part of the stomach that may store and/or commence the digestion of food before it progresses to the gizzard. The primary function of the proventriculus is to secrete hydrochloric acid (HCl) and digestive enzymes such as pepsinogen into the digestive compartments that will churn the ingested material through muscular mechanisms. Thomas Cecere (College of Veterinary Medicine of Virginia Tech) says of the proventriculus: The proventriculus is the glandular portion of the avian compound stomach, and a rather peculiar organ it is. There's nothing like it in mammals. Sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharyngeal Teeth
Pharyngeal teeth are teeth in the pharyngeal arch of the throat of cyprinids, suckers, and a number of other fish species otherwise lacking teeth."Suckers ''Catostomidae''" Iowa Department of Natural Resources Many popular aquarium fish such as and es have these structures. Members of the genus '' Botia'' such as [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acicula
Acicula (: aciculum) are strong, stout internal chaeta A chaeta or cheta (; ) is a chitinous bristle or seta found on annelid worms, although the term is also frequently used to describe similar structures in other invertebrates such as arthropods. Polychaete annelids (''polychaeta'' literally me ...e that provide support to parapodia in polychaete annelids. References {{reflist Annelid anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unidentate
In coordination chemistry, denticity () refers to the number of donor groups in a given ligand that bind to the central metal atom in a coordination complex. In many cases, only one atom in the ligand binds to the metal, so the denticity equals one, and the ligand is said to be unidentate or monodentate. Ligands with more than one bonded atom are called multidentate or polydentate. The denticity of a ligand is described with the Greek letter κ ('kappa'). For example, κ6-EDTA describes an EDTA ligand that coordinates through 6 non-contiguous atoms. Denticity is different from hapticity because hapticity refers exclusively to ligands where the coordinating atoms are contiguous. In these cases the η ('eta') notation is used. Bridging ligands use the μ ('mu') notation. Classes Polydentate ligands are chelating agents and classified by their denticity. Some atoms cannot form the maximum possible number of bonds a ligand could make. In that case one or more binding sites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
