Connective tissue is one of the four primary types of animal tissue , along with epithelial tissue , muscle tissue , and nervous tissue . It develops mostly from the mesenchyme , derived from the mesoderm , the middle embryonic germ layer . Connective tissue is found in between other tissues everywhere in the body, including the nervous system . The three meninges , membranes that envelop the brain and spinal cord , are composed of connective tissue. Most types of connective tissue consists of three main components: elastic and collagen fibers , ground substance , and cells . Blood , and lymph are classed as specialized fluid connective tissues that do not contain fiber. All are immersed in the body water . The cells of connective tissue include fibroblasts , adipocytes , macrophages , mast cells and leukocytes .
18-506: BGN or bgn may refer to: Biglycan , a protein coded by the BGN gene Bulgarian lev , the currency of Bulgaria by ISO 4217 code The Western Balochi language (ISO code: bgn) The United States Board on Geographic Names Belaya Gora Airport (IATA: BGN), Yakutia, Russia Blessed George Napier Roman Catholic School , Banbury, UK Bridgend railway station (National Rail station code: BGN),
36-503: A main line station serving the town of Bridgend, south Wales 802.11b/g/n , a designation indicating device support for certain wireless computer networking standards Busch Grand National, former name for the NASCAR Xfinity Series Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title BGN . If an internal link led you here, you may wish to change
54-464: Is a major functional component of tendons , ligaments and aponeuroses , and is also found in highly specialized organs such as the cornea . Elastic fibers , made from elastin and fibrillin , also provide resistance to stretch forces. They are found in the walls of large blood vessels and in certain ligaments, particularly in the ligamenta flava . In hematopoietic and lymphatic tissues, reticular fibers made by reticular cells provide
72-676: Is a mix of fibrous and areolar tissue . Fibromuscular tissue is made up of fibrous tissue and muscular tissue . New vascularised connective tissue that forms in the process of wound healing is termed granulation tissue . All of the special connective tissue types have been included as a subset of fascia in the fascial system , with blood and lymph classed as liquid fascia . Bone and cartilage can be further classified as supportive connective tissue . Blood and lymph can also be categorized as fluid connective tissue , and liquid fascia . Membranes can be either of connective tissue or epithelial tissue . Connective tissue membranes include
90-665: Is a particularly important proteoglycan for binding to lipoprotein in human blood vessels, thus being a significant cause of atherosclerosis . Connective tissue The term "connective tissue" (in German, Bindegewebe ) was introduced in 1830 by Johannes Peter Müller . The tissue was already recognized as a distinct class in the 18th century. Connective tissue can be broadly classified into connective tissue proper, and special connective tissue. Connective tissue proper includes loose connective tissue, and dense connective tissue. Loose and dense connective tissue are distinguished by
108-494: Is a small leucine-rich repeat proteoglycan (SLRP) which is found in a variety of extracellular matrix tissues, including bone , cartilage and tendon . In humans, biglycan is encoded by the BGN gene which is located on the X chromosome . The name "biglycan" was proposed in an article by Fisher, Termine and Young in an article in the Journal of Biological Chemistry in 1989 because
126-408: Is believed to play a role in the mineralization of bone. Knock-out mice that have had the gene for biglycan suppressed (Bgn -/-) have an osteoporosis -like phenotype with reduced growth rate and lower bone mass than mice that can express biglycan. Biglycan core protein binds to the growth factors BMP-4 and influences its bioactivity. It has also been reported that the presence of biglycan
144-459: Is characterized by collagen fibers arranged in an orderly parallel fashion, giving it tensile strength in one direction. Dense irregular connective tissue provides strength in multiple directions by its dense bundles of fibers arranged in all directions. Special connective tissue consists of cartilage , bone , blood and lymph . Other kinds of connective tissues include fibrous, elastic, and lymphoid connective tissues. Fibroareolar tissue
162-475: Is necessary for BMP-4 to exert its effects on osteoblasts . There is also evidence that biglycan binds to TGF-beta 1 . Biglycan interacts with collagen , both via the core protein and GAG chains. It has been reported that biglycan interacts more strongly with collagen type II than collagen type I . Biglycan has been reported to compete with decorin for the same binding site on collagen . Biglycan has been shown to interact with SGCA . Biglycan
180-662: The meninges (the three membranes covering the brain and spinal cord ) and synovial membranes that line joint cavities. Mucous membranes and serous membranes are epithelial with an underlying layer of loose connective tissue. Fiber types found in the extracellular matrix are collagen fibers , elastic fibers , and reticular fibers . Ground substance is a clear, colorless, and viscous fluid containing glycosaminoglycans and proteoglycans allowing fixation of Collagen fibers in intercellular spaces. Examples of non-fibrous connective tissue include adipose tissue (fat) and blood . Adipose tissue gives "mechanical cushioning" to
198-438: The proteoglycan contained two GAG chains; formerly it was known as proteoglycan-I (PG-I). Biglycan consists of a protein core containing leucine-rich repeat regions and two glycosaminoglycan (GAG) chains consisting of either chondroitin sulfate (CS) or dermatan sulfate (DS) , with DS being more abundant in most connective tissues . The CS/DS chains are attached at amino acids 5 and 10 in human biglycan. The composition of
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#1732852399912216-420: The stroma —or structural support—for the parenchyma (that is, the bulk of functional substance) of the organ. Mesenchyme is a type of connective tissue found in developing organs of embryos that is capable of differentiation into all types of mature connective tissue. Another type of relatively undifferentiated connective tissue is the mucous connective tissue known as Wharton's jelly , found inside
234-486: The umbilical cord . This tissue is no longer present after birth, leaving only scattered mesenchymal cells throughout the body. Various types of specialized tissues and cells are classified under the spectrum of connective tissue, and are as diverse as brown and white adipose tissue , blood , cartilage and bone . Cells of the immune system—such as macrophages , mast cells , plasma cells , and eosinophils —are found scattered in loose connective tissue, providing
252-528: The GAG chains has been reported as varying according to tissue of origin. Non-glycanated forms of biglycan (no GAG chains) increase with age in human articular cartilage . The composition of GAG chains of biglycan and decorin originating from the same tissue has been reported to be similar. The structure of biglycan core protein is highly conserved across species; over 90% homology has been reported for rat, mouse, bovine and human biglycan core proteins. Biglycan
270-452: The body, among other functions. Although there is no dense collagen network in adipose tissue, groups of adipose cells are kept together by collagen fibers and collagen sheets in order to keep fat tissue under compression in place (for example, the sole of the foot). Both the ground substance and proteins (fibers) create the matrix for connective tissue. Type I collagen is present in many forms of connective tissue, and makes up about 25% of
288-511: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=BGN&oldid=1217008239 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Biglycan 633 12111 ENSG00000182492 ENSMUSG00000031375 P21810 P28653 NM_001711 NM_007542 NP_001702 NP_031568 Biglycan
306-511: The ratio of ground substance to fibrous tissue. Loose connective tissue has much more ground substance and a relative lack of fibrous tissue, while the reverse is true of dense connective tissue. Loose connective tissue includes reticular connective tissue , and adipose tissue . Dense connective tissue also known as fibrous tissue is subdivided into dense regular and dense irregular connective tissue . Dense regular connective tissue, found in structures such as tendons and ligaments ,
324-612: The total protein content of the mammalian body. Connective tissue has a wide variety of functions that depend on the types of cells and the different classes of fibers involved. Loose and dense irregular connective tissue , formed mainly by fibroblasts and collagen fibers , have an important role in providing a medium for oxygen and nutrients to diffuse from capillaries to cells, and carbon dioxide and waste substances to diffuse from cells back into circulation. They also allow organs to resist stretching and tearing forces. Dense regular connective tissue , which forms organized structures,
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