{"id":41995,"date":"2023-08-03T15:08:43","date_gmt":"2023-08-03T09:23:43","guid":{"rendered":"https:\/\/microbenotes.com\/capillaries\/"},"modified":"2023-08-03T15:08:43","modified_gmt":"2023-08-03T09:23:43","slug":"capillaries","status":"publish","type":"post","link":"https:\/\/microbenotes.com\/capillaries\/","title":{"rendered":"Capillaries: Structure, 3 Types, Functions, Diseases"},"content":{"rendered":"\n<p><strong>Capillaries are incredibly small and finer blood vessels connecting the arterioles with the venules. They are the smallest blood vessels in our body.<\/strong><\/p>\n\n\n\n<p>Though it seems to be the branch of <a href=\"https:\/\/microbenotes.com\/arteries\/\" data-type=\"post\" data-id=\"41066\">arteries<\/a> and <a href=\"https:\/\/microbenotes.com\/veins\/\" data-type=\"post\" data-id=\"41082\">veins<\/a>, they are structurally and functionally different than both arteries and veins.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2023\/06\/Capillaries.jpg\" alt=\"Capillaries\" class=\"wp-image-41112\"\/><figcaption class=\"wp-element-caption\">Capillaries<\/figcaption><\/figure>\n\n\n\n<p>Despite their tiny appearance, they play crucial roles in circulation, gaseous exchange, and nutrient exchange processes. These are the sites where there is an exchange of nutrients, gases, water, wastes, hormones, and other components between cells or tissues and the <a href=\"https:\/\/microbenotes.com\/blood-components-formation-functions\/\" data-type=\"post\" data-id=\"40548\">blood<\/a>.\u00a0<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title \" >Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #0a0a0a;color:#0a0a0a\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #0a0a0a;color:#0a0a0a\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/microbenotes.com\/capillaries\/#structure-of-capillaries\" title=\"Structure of Capillaries\">Structure of Capillaries<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/microbenotes.com\/capillaries\/#types-of-capillaries\" title=\"Types of Capillaries\">Types of Capillaries<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/microbenotes.com\/capillaries\/#1-continuous-capillaries\" title=\"1. Continuous Capillaries\">1. Continuous Capillaries<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/microbenotes.com\/capillaries\/#2-fenestrated-capillaries\" title=\"2. Fenestrated Capillaries\">2. Fenestrated Capillaries<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/microbenotes.com\/capillaries\/#3-sinusoidal-capillaries\" title=\"3. Sinusoidal Capillaries\">3. Sinusoidal Capillaries<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/microbenotes.com\/capillaries\/#functions-of-capillaries\" title=\"Functions of Capillaries\">Functions of Capillaries<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/microbenotes.com\/capillaries\/#capillaries-associated-diseases\" title=\"Capillaries-associated Diseases\">Capillaries-associated Diseases<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/microbenotes.com\/capillaries\/#references\" title=\"References\">References<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"structure-of-capillaries\"><\/span><strong>Structure of Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul>\n<li>Capillaries are extremely small, so they are not clearly visible to the naked eye. They have a diameter of just 5 to 10\u03bcm.<\/li>\n\n\n\n<li>Unlike other blood vessels, their wall is made of <strong>tunica intima, which is<\/strong> composed of a very thin layer of simple squamous endothelial cells. This thin wall makes them finer to reach between the cells and provides their permeability.\u00a0<\/li>\n\n\n\n<li>They don\u2019t have any valves. They have a narrow lumen that helps them hold the blood longer to complete the nutrient\/gaseous exchange process.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"types-of-capillaries\"><\/span><strong>Types of Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Based on their structure, capillaries are classified into three types: continuous capillaries, fenestrated capillaries, and sinusoidal capillaries.\u00a0<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"1-continuous-capillaries\"><\/span><strong>1. Continuous Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>These capillaries have an uninterrupted lining (without any gaps in their wall) of endothelial cells in their walls. They are the most common types of capillaries, abundantly found in skeletal muscles, lungs, skins, gonads, and the central nervous system.\u00a0<\/p>\n\n\n\n<p>They limit the permeability of larger molecules and only allow smaller molecules like water and ions.&nbsp;&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"2-fenestrated-capillaries\"><\/span><strong>2. Fenestrated Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>These are the capillaries with the pores (fenestrae) of 60 to 80 nm covered with the diaphragm of fibrils. In the capillaries of the glomerulus, the diaphragm is replaced with the slit opening system. These pores increase their permeability, allowing them for rapid exchange of molecules. They also help exchange smaller molecules, smaller proteins, and water molecules.\u00a0<\/p>\n\n\n\n<p>They are mostly found in the kidneys, endocrine glands, pancreas, and intestines, where a rapid exchange of water and other molecules is needed.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"3-sinusoidal-capillaries\"><\/span><strong>3. Sinusoidal Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>These capillaries have a discontinuous, irregularly shaped endothelial lining with large open pores. The pores may be up to 30 to 40 \u03bcm. They are primarily located in the spleen, liver, bone marrow, brain, and lymphoid organs. They allow for the exchange of various small and larger molecules, including blood cells and serum proteins.\u00a0<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"functions-of-capillaries\"><\/span><strong>Functions of Capillaries<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul>\n<li>The major function of capillaries is facilitating the exchange of gases and nutrients between the bloodstream and tissues\/cells.\u00a0<\/li>\n\n\n\n<li>They form the blood-brain barrier, transferring selected and required components to the brain.<\/li>\n\n\n\n<li>They intake the wastes from cells and tissues and transport them to the venous system for elimination from the body.&nbsp;<\/li>\n\n\n\n<li>They also play important roles in distributing hormones to the respective targeted location.&nbsp;&nbsp;<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"capillaries-associated-diseases\"><\/span><strong>Capillaries-associated Diseases<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Capillaries may suffer from several medical conditions, of which some common types are summarized below.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Disease&nbsp;<\/strong><\/td><td><strong>Introduction<\/strong><\/td><\/tr><tr><td><strong>Capillary Leak Syndrome (Clarkson\u2019s Disease)<\/strong><\/td><td>Condition when the blood leaks from capillaries into the surrounding tissues.&nbsp;<\/td><\/tr><tr><td><strong>Capillary Hemangioma&nbsp;<\/strong><\/td><td>A benign capillary-associated tumor in infants.&nbsp;<\/td><\/tr><tr><td><strong>Hereditary Hemorrhagic Telangiectasia<\/strong><\/td><td>A condition lacking intervening capillaries resulting in a lack of connection between arterioles and venules.&nbsp;<\/td><\/tr><tr><td><strong>Microangiopathy&nbsp;<\/strong><\/td><td>A condition when the capillary wall becomes thicker and weaker so that they bleed and leak.&nbsp;<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"references\"><\/span><strong>References<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ol>\n<li>Ross &amp; Wilson Anatomy &amp; Physiology in Health and Illness. 13th ed. Churchill Livingstone Elsevier. ISBN 978-0-7020-7276-5<\/li>\n\n\n\n<li>Koka K, Patel BC. Capillary Infantile Hemangiomas. [Updated 2023 Feb 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK538249\/<\/li>\n\n\n\n<li>McDonald J, Stevenson DA. Hereditary Hemorrhagic Telangiectasia. 2000 Jun 26 [Updated 2021 Nov 24]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews\u00ae [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2023. Available from: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK1351\/<\/li>\n\n\n\n<li>Microangiopathy. (2023, May 5). In Wikipedia. https:\/\/en.wikipedia.org\/wiki\/Microangiopathy<\/li>\n\n\n\n<li>https:\/\/www.rxlist.com\/microangiopathy\/definition.htm<\/li>\n\n\n\n<li><a href=\"https:\/\/my.clevelandclinic.org\/health\/diseases\/22712-capillary-leak-syndrome\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/my.clevelandclinic.org\/health\/diseases\/22712-capillary-leak-syndrome<\/a><\/li>\n\n\n\n<li>Function of Capillaries: Definition, Structure, Types, and Conditions (healthline.com)<\/li>\n\n\n\n<li>Capillaries &#8211; Structure &amp; Function Explained with Diagrams (teachpe.com)<\/li>\n\n\n\n<li>3 Types of Capillaries (Plus Interesting Facts) \u2013 Nayturr<\/li>\n\n\n\n<li>The Function of Capillaries in the Circulatory System | Actforlibraries.org<\/li>\n\n\n\n<li>Capillaries Overview &amp; Function | What are Capillaries? &#8211; Video &amp; Lesson Transcript | Study.com<\/li>\n\n\n\n<li>Capillary. (2023, May 5). In Wikipedia. https:\/\/en.wikipedia.org\/wiki\/Capillary<\/li>\n\n\n\n<li>Capillaries: Anatomy, Function, and Significance (verywellhealth.com)<\/li>\n\n\n\n<li>What does capillary mean? (definitions.net)<\/li>\n\n\n\n<li>Capillaries: Continuous, fenestrated and sinusoidal | Kenhub<\/li>\n\n\n\n<li>Capillaries &#8211; Structure and function of arteries, capillaries and veins &#8211; Higher Human Biology Revision &#8211; BBC Bitesize<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Capillaries are incredibly small and finer blood vessels connecting the arterioles with the venules. They are the smallest blood vessels in our body. Though it seems to be the branch &#8230; <a title=\"Capillaries: Structure, 3 Types, Functions, Diseases\" class=\"read-more\" href=\"https:\/\/microbenotes.com\/capillaries\/\" aria-label=\"Read more about Capillaries: Structure, 3 Types, Functions, Diseases\">Read more<\/a><\/p>\n","protected":false},"author":16,"featured_media":41994,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6190],"tags":[],"custom":{"td_video":"","featured_image":"https:\/\/microbenotes.com\/wp-content\/uploads\/2023\/06\/Capillaries.jpg","author":{"name":"Prashant Dahal","avatar":"https:\/\/secure.gravatar.com\/avatar\/073138ccb44be2c7f33850b8ad66e8a0?s=96&d=mm&r=g"},"categories":[{"term_id":6190,"name":"Human Anatomy and Physiology","slug":"anatomy-and-physiology","term_group":0,"term_taxonomy_id":6190,"taxonomy":"category","description":"<strong>Human anatomy is the science that deals with the physical morphology and structure of the human body.<\/strong>\r\n\r\nHuman anatomy is further divided into two groups; gross anatomy and microscopic anatomy. Gross anatomy involves study related to anatomical structures that can be seen with unaided eyes, while microscopic anatomy is the study of minute anatomical structures, histology, and cytology.\r\nHumans belong to the Subphylum Vertebrate of the Phylum Chordata as they have the characteristic internal skeleton with a backbone of vertebrae.\r\nOther typical mammalian structures in humans include hair, mammary glands, and highly developed sense organs.\r\nBesides, among mammals, humans have a predominantly two-legged (bipedal) posture, along with a highly developed intellectual.\r\nThe chemical composition of the human body is composed of water and organic compounds like proteins, carbohydrates, and lipids.\r\nThe human body is composed of specialized systems for different purposes; the digestive system for digestion, the respiratory system for respiration, the reproductive system for reproduction, and the skeletal and muscular system for movement.\r\nCells are the fundamental units of the human body consisting of trillions of cells in the body. The cells together form tissues.\r\nFour basic types of tissues are found in humans, each of which is specialized for a particular purpose; epithelial tissue for covering the body, muscular tissue for movement, nerve tissues for signaling, and connective tissue for transport of nutrients.\r\nThe following organization of the human body is organs. An organ is composed of a group of specialized tissues from a structural and functional unit.\r\nOrgans are followed by the system as the final organization of the human body. The body includes nine major organ systems, each composed of various organs and tissues that work together as a functional unit.\r\nInformation on human anatomy is essential during the analysis of signs of symptoms of different diseases and disease diagnoses.\r\nIt also allows an understanding of the relationship between different organ systems and the changes occurring in the body's anatomy during growth.\r\n\r\n<strong>Human physiology is a branch of natural science that deals with the functioning of the human body.<\/strong>\r\n\r\nIt includes various physiological activities like digestion, respiration, spermatogenesis, oogenesis, and excretion, all of which occur in a coordinated way between various organs and systems.\r\nPhysiology includes the mechanical, physical, bioelectrical, and biochemical functioning of a healthy human body.\r\nA normal human body works as a result of the regulated system of networking between different systems. These interactions work towards maintaining homeostasis.\r\nThe concept of homeostasis is important in human physiology as it explains that the internal environment of an organism moves in a direction to maintain an equilibrium.\r\nIn the human body, homeostasis is maintained at the system level with each system trying to maintain its homeostasis.\r\nHuman physiology, like human anatomy, describes the mechanisms from the molecular to the cellular level, integrating the working of the entire body.\r\nBased on the information obtained via studies done on human physiology, it is understood that the cells, tissues, organs, and systems together work to maintain a healthy human body.\r\nBesides, certain compounds or chemicals produced in the body like enzymes and hormones also aid in the process of human physiology.\r\nA slight change in the working of a single organ in the body might affect the working of the entire body overall.\r\nHuman physiology is closely related to human anatomy where the anatomy of an organ or tissue plays a significant role in the physiology of the said organ or tissue.\r\nHuman physiology is also interrelated with clinical medicine and microbiology where different microorganisms found within the body aid in different processes like bacteria in the gut producing acid and other enzymes that aid in digestion.\r\nDuring the life cycle of humans, the body undergoes multiple changes which are influenced by changes in anatomy and changes in environmental factors.\u00a0 The physiology of the body thus adapts to such changes to maintain homeostasis.","parent":0,"count":74,"filter":"raw","cat_ID":6190,"category_count":74,"category_description":"<strong>Human anatomy is the science that deals with the physical morphology and structure of the human body.<\/strong>\r\n\r\nHuman anatomy is further divided into two groups; gross anatomy and microscopic anatomy. Gross anatomy involves study related to anatomical structures that can be seen with unaided eyes, while microscopic anatomy is the study of minute anatomical structures, histology, and cytology.\r\nHumans belong to the Subphylum Vertebrate of the Phylum Chordata as they have the characteristic internal skeleton with a backbone of vertebrae.\r\nOther typical mammalian structures in humans include hair, mammary glands, and highly developed sense organs.\r\nBesides, among mammals, humans have a predominantly two-legged (bipedal) posture, along with a highly developed intellectual.\r\nThe chemical composition of the human body is composed of water and organic compounds like proteins, carbohydrates, and lipids.\r\nThe human body is composed of specialized systems for different purposes; the digestive system for digestion, the respiratory system for respiration, the reproductive system for reproduction, and the skeletal and muscular system for movement.\r\nCells are the fundamental units of the human body consisting of trillions of cells in the body. The cells together form tissues.\r\nFour basic types of tissues are found in humans, each of which is specialized for a particular purpose; epithelial tissue for covering the body, muscular tissue for movement, nerve tissues for signaling, and connective tissue for transport of nutrients.\r\nThe following organization of the human body is organs. An organ is composed of a group of specialized tissues from a structural and functional unit.\r\nOrgans are followed by the system as the final organization of the human body. The body includes nine major organ systems, each composed of various organs and tissues that work together as a functional unit.\r\nInformation on human anatomy is essential during the analysis of signs of symptoms of different diseases and disease diagnoses.\r\nIt also allows an understanding of the relationship between different organ systems and the changes occurring in the body's anatomy during growth.\r\n\r\n<strong>Human physiology is a branch of natural science that deals with the functioning of the human body.<\/strong>\r\n\r\nIt includes various physiological activities like digestion, respiration, spermatogenesis, oogenesis, and excretion, all of which occur in a coordinated way between various organs and systems.\r\nPhysiology includes the mechanical, physical, bioelectrical, and biochemical functioning of a healthy human body.\r\nA normal human body works as a result of the regulated system of networking between different systems. These interactions work towards maintaining homeostasis.\r\nThe concept of homeostasis is important in human physiology as it explains that the internal environment of an organism moves in a direction to maintain an equilibrium.\r\nIn the human body, homeostasis is maintained at the system level with each system trying to maintain its homeostasis.\r\nHuman physiology, like human anatomy, describes the mechanisms from the molecular to the cellular level, integrating the working of the entire body.\r\nBased on the information obtained via studies done on human physiology, it is understood that the cells, tissues, organs, and systems together work to maintain a healthy human body.\r\nBesides, certain compounds or chemicals produced in the body like enzymes and hormones also aid in the process of human physiology.\r\nA slight change in the working of a single organ in the body might affect the working of the entire body overall.\r\nHuman physiology is closely related to human anatomy where the anatomy of an organ or tissue plays a significant role in the physiology of the said organ or tissue.\r\nHuman physiology is also interrelated with clinical medicine and microbiology where different microorganisms found within the body aid in different processes like bacteria in the gut producing acid and other enzymes that aid in digestion.\r\nDuring the life cycle of humans, the body undergoes multiple changes which are influenced by changes in anatomy and changes in environmental factors.\u00a0 The physiology of the body thus adapts to such changes to maintain homeostasis.","cat_name":"Human Anatomy and Physiology","category_nicename":"anatomy-and-physiology","category_parent":0}]},"_links":{"self":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41995"}],"collection":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/comments?post=41995"}],"version-history":[{"count":0,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41995\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media\/41994"}],"wp:attachment":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media?parent=41995"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/categories?post=41995"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/tags?post=41995"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}