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Situs Solitus
Situs solitus () is the medical term referring to the normal position of thoracic and abdominal organs. Anatomically, this means that the heart is on the left with the pulmonary atrium on the right and the systemic atrium on the left along with the cardiac apex. Right-sided organs are the liver, the gall bladder and a trilobed lung as well as the inferior vena cava, while left-sided organs are the stomach, single spleen, a bilobed lung, and the aorta. Variants on the normal picture are relatively uncommon. Complete reversal of all organs is known as situs inversus, while reversal of some organs but not others is called situs ambiguus or heterotaxy. Isolated reversal of the heart with normally-patterned viscera otherwise is termed dextrocardia. Development Although much of humans' external anatomy is bilaterally symmetric, many internal structures must be signaled to develop asymmetrically in order to form the normal situs solitus orientation. This induced asymmetry is thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Projections Of The Organs Of The Trunk
A surface, as the term is most generally used, is the outermost or uppermost layer of a physical object or space. It is the portion or region of the object that can first be perceived by an observer using the senses of Visual perception, sight and Somatosensory system, touch, and is the portion with which other materials first interact. The surface of an object is more than "a mere geometric solid", but is "filled with, spread over by, or suffused with perceivable qualities such as color and warmth". The concept of surface has been abstracted and formalized in mathematics, specifically in geometry. Depending on the properties on which the emphasis is given, there are several inequivalent such formalizations that are all called ''surface'', sometimes with a qualifier such as algebraic surface, smooth surface or fractal surface. The concept of surface and its mathematical abstractions are both widely used in physics, engineering, computer graphics, and many other disciplines, pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomical Variation
An anatomical variation, anatomical variant, or anatomical variability is a presentation of body structure with Morphology (biology), morphological features different from those that are typically described in the majority of individuals. Anatomical variations are categorized into three types including morphometric (size or shape), consistency (present or absent), and spatial (proximal/distal or right/left). Variations are seen as normal in the sense that they are found consistently among different individuals, are mostly without symptoms, and are termed anatomical variations rather than abnormalities. Anatomical variations are mainly caused by genetics and may vary considerably between different populations. The rate of variation considerably differs between single organ (anatomy), organs, particularly in muscles. Knowledge of anatomical variations is important in order to distinguish them from pathological conditions. A very early paper published in 1898, presented anatomic var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality (mathematics)
In geometry, a figure is chiral (and said to have chirality) if it is not identical to its mirror image, or, more precisely, if it cannot be mapped to its mirror image by Rotation (mathematics), rotations and Translation (geometry), translations alone. An object that is not chiral is said to be ''achiral''. A chiral object and its mirror image are said to be enantiomorphs. The word ''chirality'' is derived from the Greek (cheir), the hand, the most familiar chiral object; the word ''enantiomorph'' stems from the Greek (enantios) 'opposite' + (morphe) 'form'. Examples Some chiral three-dimensional objects, such as the helix, can be assigned a right or left handedness, according to the right-hand rule. Many other familiar objects exhibit the same chiral symmetry of the human body, such as gloves and shoes. Right shoes differ from left shoes only by being mirror images of each other. In contrast thin gloves may not be considered chiral if you can wear them wiktionary:inside ou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Situs Ambiguus
Situs ambiguus (), or heterotaxy, is a rare congenital defect in which the major visceral organs are distributed abnormally within the chest and abdomen. Clinically, heterotaxy spectrum generally refers to any defect of left-right asymmetry and arrangement of the visceral organs; however, classical heterotaxy requires multiple organs to be affected. This does not include the congenital defect situs inversus, which results when arrangement of all the organs in the abdomen and chest are mirrored, so the positions are opposite the normal placement. Situs inversus is the mirror image of situs solitus, which is normal asymmetric distribution of the abdominothoracic visceral organs. Situs ambiguus can also be subdivided into left-isomerism and right-isomerism based on the defects observed in the spleen, lungs and atria of the heart. Individuals with situs inversus or situs solitus do not experience fatal dysfunction of their organ systems, as general anatomy and morphology of the abdo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Situs Inversus
''Situs inversus'' (also called ''situs transversus'' or ''oppositus'') is a Congenital disorder, congenital condition in which the major Organ (anatomy), visceral organs are reversed or mirror image, mirrored from their normal positions. The normal arrangement of internal organs is known as ''situs solitus''. Although cardiac problems are more common, many people with ''situs inversus'' have no medical symptoms or complications resulting from the condition, and until the advent of modern medicine, it was usually undiagnosed. ''Situs inversus'' is found in about 0.01% of the population, or about 1 person in 10,000. In the most common situation, ''situs inversus totalis'', it involves complete transposition (right to left reversal) of all of the viscera. The heart is not in its usual position in the left chest, but is on the right, a condition known as ''dextrocardia'' (). Because the relationship between the organs is not changed, most people with ''situs inversus'' have no associa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yasushi Okada
Yasuji Okada (born 1968) is a Japanese molecular biologist and physician. He is a professor at the University of Tokyo. He is known for his research in single-molecule biology and bioimage informatics, notably discovering that kinesin can move as a single molecule. Collaborating with Olympus, he also developed a high-speed, high-resolution spinning disk super-resolution microscopy technique. He is the chief researcher at the University of Tokyo's International Research Centre for Neurointelligence, leading the ''Information Physics of Living Matters project''. This project had already secured 1.15 billion yen (approximately US$10 million) of government research grant before it started. Career Okada entered Nada Junior High School in 1981 and Nada High School in 1984. Commuting by train from his home in Osaka, he spent his travel time reading extensively. During his high school years, he read "Mechanics" by Landau and Lifshitz, part of the Course of Theoretical Physics series, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nodal Cilia
The cilium (: cilia; ; in Medieval Latin and in anatomy, ''cilium'') is a short hair-like membrane protrusion from many types of eukaryotic cell. (Cilia are absent in bacteria and archaea.) The cilium has the shape of a slender threadlike projection that extends from the surface of the much larger cell body. Eukaryotic flagella found on sperm cells and many protozoans have a similar structure to motile cilia that enables swimming through liquids; they are longer than cilia and have a different undulating motion. There are two major classes of cilia: ''motile'' and ''non-motile'' cilia, each with two subtypes, giving four types in all. A cell will typically have one primary cilium or many motile cilia. The structure of the cilium core, called the axoneme, determines the cilium class. Most motile cilia have a central pair of single microtubules surrounded by nine pairs of double microtubules called a 9+2 axoneme. Most non-motile cilia have a 9+0 axoneme that lacks the central pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NODAL
Nodal may refer to: * Nodal, the adjectival form of the noun :wikt:node * Nodal homolog, a protein encoded by the gene NODAL and responsible for left-right asymmetry * Nodal (software), a novel music composition program * Christian Nodal (born 1999), Mexican singer and songwriter {{Disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphogens
A morphogen is a substance whose non-uniform distribution governs the Natural patterns, pattern of tissue development in the process of morphogenesis or pattern formation, one of the core processes of developmental biology, establishing positions of the various specialized cell types within a tissue. More specifically, a morphogen is a signaling molecule that acts directly on cells to produce specific cellular responses depending on its local concentration. Typically, morphogens are produced by source cells and diffuse through surrounding tissues in an embryo during early development, such that concentration gradients are set up. These gradients drive the process of differentiation of unspecialised stem cells into different cell types, ultimately forming all the tissues and organs of the body. The control of morphogenesis is a central element in evolutionary developmental biology (evo-devo). History The term was coined by Alan Turing in the paper "The Chemical Basis of Morpho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bilateral Symmetry
Symmetry in biology refers to the symmetry observed in organisms, including plants, animals, fungi, and bacteria. External symmetry can be easily seen by just looking at an organism. For example, the face of a human being has a plane of symmetry down its centre, or a pine cone displays a clear symmetrical spiral pattern. Internal features can also show symmetry, for example the tubes in the human body (responsible for transporting gases, nutrients, and waste products) which are cylindrical and have several planes of symmetry. Biological symmetry can be thought of as a balanced distribution of duplicate body parts or shapes within the body of an organism. Importantly, unlike in mathematics, symmetry in biology is always approximate. For example, plant leaves – while considered symmetrical – rarely match up exactly when folded in half. Symmetry is one class of patterns in nature whereby there is near-repetition of the pattern element, either by Reflection (geometry), reflect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dextrocardia
Dextrocardia () is a rare congenital condition in which the apex of the heart is located on the right side of the body, rather than the more typical placement towards the left. There are two main types of dextrocardia: dextrocardia of embryonic arrest (also known as isolated dextrocardia) and dextrocardia ''situs inversus''. Dextrocardia ''situs inversus'' is further divided. Classification Dextrocardia of embryonic arrest In this form of dextrocardia, the heart is simply placed further right in the thorax than is normal. It is commonly associated with severe defects of the heart and related abnormalities including pulmonary hypoplasia. Dextrocardia situs solitus Dextrocardia refers to a heart positioned in the right side of the chest. Situs solitus describes viscera that are in the normal position, with the stomach on the left side. Dextrocardia situs inversus Dextrocardia situs inversus refers to the heart being a mirror image situated on the right side. For all visceral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
