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Premaxilla
The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has been usually termed as the incisive bone. Other terms used for this structure include premaxillary bone or ''os premaxillare'', intermaxillary bone or ''os intermaxillare'', and Goethe's bone. Human anatomy In human anatomy, the premaxilla is referred to as the incisive bone (') and is the part of the maxilla which bears the incisor teeth, and encompasses the anterior nasal spine and alar region. In the nasal cavity, the premaxillary element projects higher than the maxillary element behind. The palatal portion of the premaxilla is a bony plate with a generally transverse orientation. The incisive foramen is bound anteriorly and laterally by the premaxilla and posteriorly by the palatine process of the maxilla. It is formed from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisive Bone
The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has been usually termed as the incisive bone. Other terms used for this structure include premaxillary bone or ''os premaxillare'', intermaxillary bone or ''os intermaxillare'', and Goethe's bone. Human anatomy In human anatomy, the premaxilla is referred to as the incisive bone (') and is the part of the maxilla which bears the incisor teeth, and encompasses the anterior nasal spine and alar region. In the nasal cavity, the premaxillary element projects higher than the maxillary element behind. The palatal portion of the premaxilla is a bony plate with a generally transverse orientation. The incisive foramen is bound anteriorly and laterally by the premaxilla and posteriorly by the palatine process of the maxilla. It is formed from the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Structure In humans, the maxilla consists of: * The body of the maxilla * Four processes ** the zygomatic process ** the frontal process of maxilla ** the alveolar process ** the palatine process * three surfaces – anterior, posterior, medial * the Infraorbital foramen * the maxillary sinus * the incisive foramen Articulations Each maxilla articulates with nine bones: * two of the cranium: the frontal and ethmoid * seven of the face: the nasal, zygomatic, lacrimal, inferior n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinosaurus Aegyptiacus
''Spinosaurus'' (; ) is a genus of spinosaurid dinosaur that lived in what now is North Africa during the Cenomanian to upper Turonian stages of the Late Cretaceous period, about 99 to 93.5 million years ago. The genus was known first from Egyptian remains discovered in 1912 and described by German palaeontologist Ernst Stromer in 1915. The original remains were destroyed in World War II, but additional material came to light in the early 21st century. It is unclear whether one or two species are represented in the fossils reported in the scientific literature. The best known species is ''S. aegyptiacus'' from Egypt, although a potential second species, ''S. maroccanus'', has been recovered from Morocco. The contemporary spinosaurid genus ''Sigilmassasaurus'' has also been synonymized by some authors with ''S. aegyptiacus'', though other researchers propose it to be a distinct taxon. Another possible junior synonym is ''Oxalaia'' from the Alcântara Formation in Brazil. ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleft Lip And Palate
A cleft lip contains an opening in the upper lip that may extend into the nose. The opening may be on one side, both sides, or in the middle. A cleft palate occurs when the palate (the roof of the mouth) contains an opening into the nose. The term orofacial cleft refers to either condition or to both occurring together. These disorders can result in feeding problems, speech problems, hearing problems, and frequent ear infections. Less than half the time the condition is associated with other disorders. Cleft lip and palate are the result of tissues of the face not joining properly during development. As such, they are a type of birth defect. The cause is unknown in most cases. Risk factors include smoking during pregnancy, diabetes, obesity, an older mother, and certain medications (such as some used to treat seizures). Cleft lip and cleft palate can often be diagnosed during pregnancy with an ultrasound exam. A cleft lip or palate can be successfully treated with surge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cranial Bone
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the front ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisive Foramen
In the human mouth, the incisive foramen (also known as: "''anterior palatine foramen''", or "''nasopalatine foramen''") is the opening of the incisive canals on the hard palate immediately behind the incisor teeth. It gives passage to blood vessels and nerves. The incisive foramen is situated within the incisive fossa of the maxilla. The incisive foramen is used as an anatomical landmark for defining the severity of cleft lip and cleft palate. The incisive foramen exists in a variety of species. Structure The incisive foramen is a funnel-shaped opening of the in the bone of the oral hard palate representing the inferior termination of the incisive canal. An oral prominence - the incisive papilla - overlies the incisive fossa. The incisive foramen is situated immediately behind the incisor teeth, and in between the two premaxillae. Contents The incisive foramen allows for blood vessels and nerves to pass. These include: * the pterygopalatine nerves to the hard palate. * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisor
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, whereas armadillos have none. Structure Adult humans normally have eight incisors, two of each type. The types of incisor are: * maxillary central incisor (upper jaw, closest to the center of the lips) * maxillary lateral incisor (upper jaw, beside the maxillary central incisor) * mandibular central incisor (lower jaw, closest to the center of the lips) * mandibular lateral incisor (lower jaw, beside the mandibular central incisor) Children with a full set of deciduous teeth (primary teeth) also have eight incisors, named the same way as in permanent teeth. Young children may have from zero to eight incisors depending on the stage of their tooth eruption and tooth development. Typically, the mandibular central incisors erupt first, followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Wolfgang Von Goethe
Johann Wolfgang von Goethe (28 August 1749 – 22 March 1832) was a German poet, playwright, novelist, scientist, statesman, theatre director, and critic. His works include plays, poetry, literature, and aesthetic criticism, as well as treatises on botany, anatomy, and colour. He is widely regarded as the greatest and most influential writer in the German language, his work having a profound and wide-ranging influence on Western literary, political, and philosophical thought from the late 18th century to the present day.. Goethe took up residence in Weimar in November 1775 following the success of his first novel, ''The Sorrows of Young Werther'' (1774). He was ennobled by the Duke of Saxe-Weimar, Karl August, in 1782. Goethe was an early participant in the ''Sturm und Drang'' literary movement. During his first ten years in Weimar, Goethe became a member of the Duke's privy council (1776–1785), sat on the war and highway commissions, oversaw the reopening of silver min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Process
The alveolar process () or alveolar bone is the thickened ridge of bone that contains the tooth sockets on the jaw bones (in humans, the maxilla and the mandible). The structures are covered by gums as part of the oral cavity. The synonymous terms ''alveolar ridge'' and ''alveolar margin'' are also sometimes used more specifically to refer to the ridges on the inside of the mouth which can be felt with the tongue, either on roof of the mouth between the upper teeth and the hard palate or on the bottom of the mouth behind the lower teeth. Terminology The term ''alveolar'' () ('hollow') refers to the cavities of the tooth sockets, known as dental alveoli. The alveolar process is also called the ''alveolar bone'' or ''alveolar ridge''. The curved portion is referred to as the alveolar arch. The alveolar bone proper, also called bundle bone, directly surrounds the teeth. The term alveolar crest describes the extreme rim of the bone nearest to the crowns of the teeth. The portion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankylosed
Ankylosis is a stiffness of a joint due to abnormal adhesion and rigidity of the bones of the joint, which may be the result of injury or disease. The rigidity may be complete or partial and may be due to inflammation of the tendinous or muscular structures outside the joint or of the tissues of the joint itself. When the structures outside the joint are affected, the term "false ankylosis" has been used in contradistinction to "true ankylosis", in which the disease is within the joint. When inflammation has caused the joint-ends of the bones to be fused together, the ankylosis is termed ''osseous'' or complete and is an instance of synostosis. Excision of a completely ankylosed shoulder or elbow may restore free mobility and usefulness to the limb. "Ankylosis" is also used as an anatomical term, bones being said to ankylose (or anchylose) when, from being originally distinct, they coalesce, or become so joined that no motion can take place between them. The term is from Gree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleostomi
Teleostomi is an obsolete clade of jawed vertebrates that supposedly includes the tetrapods, bony fish, and the wholly extinct acanthodian fish. Key characters of this group include an operculum and a single pair of respiratory openings, features which were lost or modified in some later representatives. The teleostomes include all jawed vertebrates except the chondrichthyans and the extinct class Placodermi. Recent studies indicate that Osteichthyes evolved from placoderms like ''Entelognathus'', while acanthodians are more closely related to modern chondrichthyes. Teleostomi, therefore, is not a valid, natural clade, but a polyphyletic group of species. The clade Teleostomi should not be confused with the similar-sounding fish clade Teleostei. Origins The origins of the teleostomes are obscure. They are traditionally assumed to be descendants of the Acanthodians ("spiny sharks") from the Early Silurian Period; however, more recent discoveries show that the "spiny sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porcupinefish
Porcupinefish are fish belonging to the family Diodontidae (order Tetraodontiformes), also commonly called blowfish and, sometimes, balloonfish and globefish. They are sometimes collectively called pufferfish, not to be confused with the morphologically similar and closely related Tetraodontidae, which are more commonly given this name. Porcupinefish are medium- to large-sized fish, and are found in shallow temperate and tropical seas worldwide. A few species are found much further out from shore, wherein large schools of thousands of individuals can occur. They are generally slow-moving. Porcupinefish have the ability to inflate their bodies by swallowing water or air, thereby becoming rounder. This increase in size (almost double vertically) reduces the range of potential predators to those with much bigger mouths. A second defense mechanism is provided by the sharp spines, which radiate outwards when the fish is inflated. Some species are poisonous, having tetrodotoxin in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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