Who has horny scales? M
Stratum corneum consists of horny scales (they are sometimes called corneocytes), which are connected to each other with the help of interpenetrating outgrowths of the membrane, especially deep on the lateral sides, and keratinized desmosomes. Each horny scale is up to 10 µm in length or more, and its thickness ranges from 100 nm to 1 µm. On the outside it is surrounded by an electron-dense shell 12-15 nm thick, and inside it is filled with keratin fibrils with a diameter of 7-8 nm, separated by electron-dense amorphous material in a 1:1 ratio.
Available two types of scales: scales with a loose filling of keratin fibrils (type B, they are located closer to the granular layer) and scales with a dense filling (type A). Individual scales immediately adjacent to the granular cells, along with bundles of keratin fibrils, sometimes contain a significant amount of keratohyalin granules and single remains of mitochondria. These scales are sometimes called T-plates.
According to its microscopic structure, this zone corresponds to the shiny layer, which is currently not distinguished by many authors as an independent layer of the epidermis. The spaces between the scales often contain an electron-dense cementing substance of glycolipin nature.
Thickness of the stratum corneum is determined by the interaction of two factors: the rate of reproduction and movement in the vertical direction of keratinocytes, on the one hand, and the rate of rejection of horny scales, on the other. With mechanical and some other effects on the skin, the mitotic activity of keratinocytes and their upward movement are activated at a normal rate of rejection of horny scales. This is how a cornea appears. In some cases of skin pathology, the processes of rejection of horny scales are disrupted at normal rates of proliferation and differentiation of keratinocytes. A group of diseases with a similar ratio of the processes of production and loss of horny scales is called hyperkeratoses.
IN lately found that scales of the stratum corneum may have columnar or non-columnar organization. A non-columnar organization is characteristic of thick skin with a thick stratum corneum. Such skin is characterized by high mitotic activity of the epidermis, which prevents the ordering of horny scales. The columnar organization of the stratum corneum is, on the contrary, characteristic of thin skin with low mitotic activity of the epidermis. Cells of all layers of the epidermis and horny scales with a columnar organization, they are located strictly above each other. Each horny scale has a hexagonal shape and each of its 6 sides is in contact with an adjacent scale (“quilt”).
This arrangement provides the best possible connection between the scales and execution by the stratum corneum permeability barrier. With a number skin diseases the normal arrangement of horny scales is disrupted. The organization of the stratum corneum in columns will be discussed in more detail when considering the epidermal proliferative unit (EPU).
SCALES
(squama), rigid metameric plates of the dermal skeleton of vertebrates - fish, reptiles, birds and some mammals, performing a protective function. The shape and structure of parts in animals of different systematics. groups are different. Ch. fossil agnathans and fishes of mesodermal origin, formed bone tissue(dentin, bone); It is located on the animal’s body in regular diagonal rows along the collagen fibers of the skin and, in addition to protective, performs a musculoskeletal function. In the phylogeny of lower vertebrates (cyclostomes, fish, amphibians), the initial placoid Ch. cartilaginous fish, from which other, more complex Ch. arose. bony fish - ganoid, including cosmoid, and bone, including cycloid and ctenoid. All types of Ch. fish are characterized by cyclic. growth with the formation of growth rings, which make it possible to determine the age and growth rate of the fish. Among amphibians, bony parts, homologous to lobe-finned fish, are known from some stegocephalians and modern fishes. legless amphibians (caecilians, fish snakes). The horny part of reptiles, birds and some mammals is formed by keratinization of the outer surface. layer of the epidermis. Horny parts are usually replaced periodically. shedding or peeling. In reptiles, the horny part sometimes fuses with secondary skin ossifications and covers the entire body (crocodiles, turtles), in birds - only the legs, in mammals (marsupials, rodents, insectivores and some others) the horn is located. arr. on the tail. Bird feathers are derivatives of horny parts. In the phylogenesis of mammals, the cover of horny parts was replaced by hair. The secondary development of powerful parts on the body is observed in armadillos (underlain by bony parts) and pangolins.
.(Source: Biological encyclopedic dictionary." Ch. ed. M. S. Gilyarov; Editorial team: A. A. Babaev, G. G. Vinberg, G. A. Zavarzin and others - 2nd ed., corrected. - M.: Sov. Encyclopedia, 1986.)
scalesCovering hard plates located in in a certain order in the skin of some vertebrates. The scales perform protective and support functions. In fish it develops from the skin itself (corium) and has a different structure and shape. The scales of cartilaginous fish are placoid, have the shape of a plate of osteodentine with a tooth covered with enamel; the teeth of these fish are modified scales. Bone scales ganoid fish– ganoid, large, rhombic or round, made of ganoid or bone substance, scales are movably articulated. Lobe-finned fish have cosmoid scales - thick bone plates covered with cosmin and enamel on top. Body sturgeon fish covered with several rows large scales in the form of bone bugs. The bony scales of ray-finned fish can be rounded - cycloid (in cypriniformes) and with teeth - ctenoid (in perciformes). The scales of bony fish grow unevenly (cyclically), forming tree rings. Among modern amphibians, legless ones (caecilians and fish snakes) have bony scales. Reptiles and birds have scales of epidermal origin in the form of horny plates - small in lizards and snakes, large in crocodiles and turtles. In birds, only the legs are covered with horny scales. In mammals (marsupials, insectivores, rodents), horny scales are located on the tail. The body of armadillos and lizards (pangolins) is densely covered with secondary scales, forming a protective shell.
.(Source: “Biology. Modern illustrated encyclopedia.” Chief editor A. P. Gorkin; M.: Rosman, 2006.)
- - fish. It is a valuable culinary product. Usually when cleaning fish they throw it away...
Great encyclopedia culinary art of Pokhlebkin
- - I. Animals that lived in or on water and did not have scales or feathers were considered unclean by the Israelites. see Purity, impurity, pure, unclean, purification. II. Scale armor, see Weapons and tools...
Brockhaus Biblical Encyclopedia
- - Fish scales symbolize armor, protection and the god Ea-Oannes, Lord of the Depths...
Dictionary of symbols
- - hard plates on the skin of vertebrates - fish, reptiles, birds and some mammals. Protects skin from damage and drying out...
Natural science. Encyclopedic Dictionary
- - rigid metameric plates of the dermal skeleton of vertebrates - fish, reptiles, birds and some mammals, performing a protective function...
Great Soviet Encyclopedia
- - hard plates on the skin of vertebrates - fish, reptiles, birds and some mammals. Protects skin from damage and drying out...
Large encyclopedic dictionary
- - other Russian scales, old glory. cheshouѩ λεπίς, Ukrainian. scaly "scaly", Polish. szczeszuja, czeżuja ", nutshell". Associated with scratching, like bolg. squama "scale"; see Bernecker I, 152; Trautman, BSW 120...
Vasmer's Etymological Dictionary
- - B ́ noun see _Appendix II scales ́ And you, deep and well-fed, Burdened with azure, Like a many-eyed one *, And the alpha and omega of the storm. O. E. Mandelstam, “And the sky is pregnant with the future.....
Dictionary of Russian accents
- - ...
Spelling dictionary of the Russian language
- - female scales, small plates or scutes different types, lying closed. Fish scales, lice. Lizards have small scales. The wings of moths are covered with scales. The lizard also has large, bone scales...
Dictionary Dahl
- - ́, -i, female Small hard plates located on the surface so that each closely covers the edge of the neighboring one...
Ozhegov's Explanatory Dictionary
- - ́, scales, pl. no, female 1. Small plates, scutes, located so that the edge of one covers part of the other. Fish scales. Bone scales. The snake shed its scales. The tiles are laid in scales. 2...
Ushakov's Explanatory Dictionary
- - scales I f. 1. A cover of small plates, scutes, arranged so that the edge of one covers part of the other. 2. Something that resembles such a coating in appearance. Ott. transfer...
Explanatory Dictionary by Efremova
- - I scratch, - "...
Russian spelling dictionary
- - Obsesslav. Suf. derivative of chesati "to separate". See scratch. Scales literally mean “that which comes off”...
Etymological Dictionary of the Russian Language
- - SCALES, -i, g. Nonsense, nonsense. To carry scales - to say or do stupid things. Poss. superposition of "" and "nonsense"...
Dictionary of Russian argot
"SCALES" in books
Fish scales are their passport
author Pravdin Ivan FedorovichFish scales are their passport
From the book The Story of a Fish author Pravdin Ivan FedorovichFish scales - their passport You probably noticed that semicircles are visible on the shell of the toothless fish (there are many of them in rivers and lakes). Each of them corresponds to one year of the animal’s life. The same rings as on the toothless shell and on the cross-cut of wood are visible on
Darwin Award: oh, tail, scales!
From the book Darwin Award. Evolution in action by Northcutt WendyDarwin Award: oh, tail, scales! 1998 Winner Not confirmed by the Darwin Commission January 29, 1998, Ohio Wednesday turned out to be a fateful day for Michael. He was chatting with his friends while one of them was cleaning the aquarium. A fish lover complained that one fish was harassing
Dried Fish Scales. To make any money good
From the book Anastasia. Items of power, luck and prosperity author Ignatova MariaDried Fish Scale. To make any money good - Much ancient knowledge is lost over time and is lost without a trace. Previously, in every house there was always a linen bag with dried fish scales hanging. Such scales were recognized as an Object of Power.
M. N. Muravyov and the “Latinizants”: “...The scales have fallen from our eyes...”
From the book Confession, Empire, Nation. Religion and the problem of diversity in history post-Soviet space author Semenov AlexanderM. N. Muravyov and the “Latinists”: “...The scales have fallen from our eyes...” The measures of the 1860s to convert Catholics in the North-Western Territory from the very beginning were little consistent with the trend towards individualization of conversions that had emerged at the same time in legislation. Thought about
Why does a snake need scales?
From the book Everything about everything. Volume 3 author Likum ArkadyWhy does a snake need scales? Snakes are reptiles, and like all reptiles, they have dry, scaly skin. Relatives of snakes include lizards, alligators, crocodiles, sea and land turtles. Since there are more than 2000 species of snakes in the world, it is not surprising that they live
From the book Big Soviet Encyclopedia(CT) by the author TSBsquama, ae f – scales
From the author's booksquama, ae f – scales Approximate pronunciation: squama.Z: Tell me, friends, Where are the frog’s SCALES? The frog says: “KWA! I have scales -
Replacement of epidermal cells occurs after 27 days and is visually imperceptible. In some dermatoses, the cells of the stratum corneum contain remnants of the nucleus, and the rejection of the stratum corneum of the epidermis becomes noticeable. These horny plates are called scales. The scales can be very small; such peeling is called pityriasis. If peeling of the stratum corneum occurs in large layers, then this is lamellar peeling.
Enhanced growth of the stratum corneum with the formation of dense, dry horny masses with prolonged exposure sun rays or friction is called hyperkeratosis. Such scales are yellow-gray or grayish-brown in color and are difficult to separate from the surface of the skin. Ichthyosis (fish scales) is manifested by generalized hyperkeratosis. Parakeratosis is a process that occurs against the background of inflammatory changes in the skin, as a result of which there is no granular layer in the epidermis and the horny plates contain remnants of nuclei.
Peeling on the scalp and extensor surface of the limbs, in which the scales are easily removed, suggests that the patient has psoriasis. With most dermatophytoses (fungal diseases), areas of peeling appear on the skin.
More on the topic of Scales:
- MEDICINAL PLANTS AND MEDICINAL PLANT RAW MATERIALS CONTAINING MAINLY ACICLIC AND ALIPHATIC MONOTERPENOIDS
Scales on the skin are secondary rashes that form after the process of evolution of the primary elements occurs. They are a cluster of horny plates of the epidermis. Depending on the size of the scales, they are divided into the following types:
Leaf-like peeling (scale size more than 5 mm);
Lamellar peeling (scale size from 1 to 5 mm);
Pityriasis peeling (small scales).
The appearance of scales on the skin can be caused by various diseases: measles, scarlet fever, seborrheic dermatitis, psoriasis. With measles and scarlet fever, making a diagnosis, as a rule, does not cause difficulties, since the occurrence of scales is directly related to the stages infectious disease accompanied by a whole range of symptoms.
With seborrheic dermatitis, the scales have their own characteristics.
Most classic version The distribution of rashes with seborrheic dermatitis is symmetry. As a rule, the pathological process affects the scalp, eyelashes, eyebrows, mustache, nasolabial folds, behind-the-ear areas, and the skin of the external auditory canals. In the torso area, seborrheic dermatitis also has its own favorite places, the rashes are localized in the navel, groin and axillary areas, in the anogenital area and on the skin under the mammary glands. Scales in seborrheic dermatitis white, mealy, small. Less commonly, large lamellar scales are observed in this disease. In severe cases of the disease, the scales are greasy and mealy in nature, and scaly crusts that have a yellowish tint may also be observed.
In psoriasis, flake formation is associated with increased proliferation of epidermal cells. The so-called parakeratosis occurs, in which cells located in lower layers, push out the overlying cells even before the keratinization process is completed. The nature of the scales in psoriasis varies depending on the clinical form of the disease. With ordinary psoriasis, the scales are loose and their color is silvery-white. In the exudative form of psoriasis, the scales are characterized by a yellowish-grayish color; they stick together, forming crusts that fit tightly to the skin.
Also, scales can appear on the skin with allergic dermatitis, demodicosis (infection with an opportunistic mite).
If scales appear on the skin, the patient needs to be examined by a dermatologist, conduct diagnostic tests, and analyze a scraping taken from the surface of the affected area of the skin. Depending on the established diagnosis, appropriate treatment is prescribed. You can get more information about diseases that are accompanied by the formation of scales in the relevant thematic sections.
Scales(squamae) - bone or horny formations in the skin of vertebrates. The initial form of the bone scales is taken to be placoid scales or cutaneous teeth of selachians, etc. These scales appear in the form of a papilla of the connective tissue layer (carii), protruding into the malpighian layer. The deep-lying cylindrical cells of this layer are distinguished on their inner surface enamel layer, and the superficial cells of the papilla, also receiving cylindrical shape and called scleroblasts, secrete dentin on their outer surface, penetrated by channels into which the processes of scleroblasts enter. Due to the connective tissue of carii, a bone plate is formed under the thus formed tooth - the main or basal one. The cavity is filled with a papilla (pulpa). These scales lie in the skin, and then become exposed and fall off, being replaced by newly formed ones. In Lepidosteus, during the development of Scales, several denticles are also laid under the Scales, but they are provisional, and as permanent organs, denticles made of dentin and enamel are also characteristic of armored catfishes from bony fishes. They have a shell of bony plates corresponding to the fused basal plates and connected to the aforementioned teeth by a layer of connective tissue, so that these teeth sit movably. In general, the scales of ganoids and teleosts were probably formed through the fusion of basal plates and the loss of denticles. In ganoids we have either skin ossifications (in sturgeons), or there are rhombic, rows of parts, called ganoids and consisting of a lower bone layer and an upper one, similar to enamel, but of a completely different origin. The development of this layer in Lepidosteus shows that this layer, called ganoid, is formed through the fusion of dentin of the provisional denticles. U bony fish scales with a rounded posterior edge or cycloid and with a comb-toothed posterior edge or ctenoid are distinguished. These scales consist of two layers: the upper one, containing bone cells and corresponding to the basal plate, and the lower one, consisting of connective tissue impregnated with lime. In bibreathes we find the same two layers, but the upper (bone) has the character of a perforated plate bearing teeth, but these teeth, apparently, do not correspond to placoid teeth. Some fish do not have Ch. In cyclostomes this may be a primary phenomenon, but in other cases (eels, Polyodon s. spatularia from ganoids) there are provisional Ch. Finally, in some catfishes and in fused-jawed animals, etc., the scaly cover is modified into a shell of bones records. In Calluchtys they are arranged in 4 regular longitudinal rows. Small bone scales amphibians have Gymnophiona (see Caecilians), and bone deposits are characteristic of some living (Ceratophrys dorsata and Ephippiger aurantiacus), as well as fossil (Stegocephala) forms. Reptiles have a characteristic horny cover. When local thickenings of the stratum corneum are closely adjacent to each other, they are called scutes, and when they overlap each other with the posterior edge, they are called scutes. The original form of these formations should be considered the papilla corii, the thickening of the stratum corneum above it (geckos, chameleons), and from This form can be used to produce scutes, scales and spines found in some lizards. Crocodiles and turtles have bone deposits under the horny deposits (see Shields of turtles). Horny formations are found in birds only on the legs, but it is not clear whether these formations represent the heritage of ancestors or are a later acquisition. The latter is more likely. Horny Scales are also characteristic of mammals. In the Manis or pangolin (of the edentates), these scales cover the entire body. Scales are preserved on the tail of some placentals (beaver, muskrat, biuterus). Armadillos and fossil edentates (Glyptodon), in addition to horny scutes, have bone deposits in the skin (head, trunk and tail). In armadillos they are connected movably and arranged in transverse rows, while in Glyptodon they were connected motionlessly. Traces of Ch. in the form of skin thickenings are observed in cetaceans (in the Indian Neomeris phocaenoides), as well as in the form of provisional formations on the tail of insectivores (Centetes). The lamellar cover of the tail of rats, etc., is apparently a secondary formation. In any case, the ancestors of mammals had scales or scutes, and the arrangement of hairs on the body in groups probably represents the result of the original arrangement of hairs on the face. The hairs were lost, but the arrangement in groups remained. Feathers are also considered as a modification of Scales (see).
V. Shimkevich.
Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron. - S.-Pb. Brockhaus-Efron.