{"id":41078,"date":"2023-08-03T14:57:41","date_gmt":"2023-08-03T09:12:41","guid":{"rendered":"https:\/\/microbenotes.com\/epithelial-tissue\/"},"modified":"2023-08-03T14:57:41","modified_gmt":"2023-08-03T09:12:41","slug":"epithelial-tissue","status":"publish","type":"post","link":"https:\/\/microbenotes.com\/epithelial-tissue\/","title":{"rendered":"Epithelial Tissue &#8211; Definition, types, functions, examples"},"content":{"rendered":"<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\/epithelial-tissue\/#epithelial-tissue-definition\" title=\"Epithelial Tissue definition\">Epithelial Tissue definition<\/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\/epithelial-tissue\/#characteristics-of-epithelial-tissue\" title=\"Characteristics of Epithelial Tissue\">Characteristics of Epithelial Tissue<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#functions-of-epithelial-tissue\" title=\"Functions of Epithelial Tissue\">Functions of Epithelial Tissue<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#types-classification-with-examples-and-location\" title=\"Types \/ Classification with examples and location\">Types \/ Classification with examples and location<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#simple-epithelium\" title=\"Simple epithelium\">Simple epithelium<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#a-simple-squamous-epithelium\" title=\"a. Simple squamous epithelium\">a. Simple squamous epithelium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#b-simple-cuboidal-epithelium\" title=\"b. Simple cuboidal epithelium\">b. Simple cuboidal epithelium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#c-simple-columnar-epithelium\" title=\"c. Simple columnar epithelium\">c. Simple columnar epithelium<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#stratified-epithelium\" title=\"Stratified epithelium\">Stratified epithelium<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#a-stratified-squamous-epithelium\" title=\"a. Stratified squamous epithelium\">a. Stratified squamous epithelium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#b-stratified-cuboidal-epithelium\" title=\"b. Stratified cuboidal epithelium\">b. Stratified cuboidal epithelium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#c-stratified-columnar-epithelium\" title=\"c. Stratified columnar epithelium\">c. Stratified columnar epithelium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#pseudostratified-columnar-epithelium\" title=\"Pseudostratified columnar epithelium\">Pseudostratified columnar epithelium<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#transitional-epithelium-tissue\" title=\"Transitional epithelium tissue\">Transitional epithelium tissue<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#glandular-epithelium\" title=\"Glandular Epithelium\">Glandular Epithelium<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#endocrine-glands\" title=\"Endocrine glands \">Endocrine glands <\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#exocrine-glands\" title=\"Exocrine glands\">Exocrine glands<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#references\" title=\"References\">References<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/#internet-sources\" title=\"Internet Sources\">Internet Sources<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"epithelial-tissue-definition\"><\/span><strong>Epithelial Tissue definition<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>Epithelial Tissue<\/strong> is one of the four types of tissue (epithelial, muscular, connective, and nervous) in animals which consists of closely aggregated polyhedral cells adhering firmly to one another, forming cellular sheets that line the interior of hollow organs and cover the body surface. An epithelial tissue or epithelium (plural is epithelia) consists of cells arranged in continuous sheets, in either single or multiple layers.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"characteristics-of-epithelial-tissue\"><\/span><strong>Characteristics of Epithelial Tissue<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Even though epithelial tissue present in different parts of the body might differ in structure and function, they all have some common characteristics.<\/li>\n<li>Some of these characteristics are given below:<\/li>\n<\/ul>\n<ol>\n<li><strong>Shape and Size<\/strong><\/li>\n<\/ol>\n<ul>\n<li>The shapes and sizes of epithelial cells are variable, ranging from tall columnar to cuboidal to low squamous.<\/li>\n<li>The cell&#8217;s size and morphology are generally based on their function.<\/li>\n<\/ul>\n<ol start=\"2\">\n<li><strong>Polarity<\/strong><\/li>\n<\/ol>\n<ul>\n<li>Epithelial cells generally show polarity, with organelles and membrane proteins distributed unevenly within the cell.<\/li>\n<li>The apical (free) surface of an epithelial cell is present towards the body surface, the body cavity, the lumen of an internal organ, or a gland duct that receives cell secretions. Apical surfaces may contain cilia or microvilli.<\/li>\n<li>The lateral surfaces of an epithelial cell, facing the adjacent cells on either side, may contain intercellular adhesion and other junctions.<\/li>\n<li>The basal surface of an epithelial cell adheres to extracellular materials such as the basement membrane, which is an inert connective tissue made by the epithelial cells themselves.<\/li>\n<\/ul>\n<ol start=\"3\">\n<li><strong>Basement Membrane<\/strong><\/li>\n<\/ol>\n<ul>\n<li>The basement membrane is a thin extracellular layer that commonly consists of two layers, the basal lamina, and the reticular lamina.<\/li>\n<li>The basal lamina is closer to and secreted by the epithelial cells and contains proteins like laminin and collagen as well as some glycoproteins and proteoglycans.<\/li>\n<li>The reticular lamina is closer to the connective tissue, present underneath, and contains collagen protein produced by connective tissue cells called fibroblasts.<\/li>\n<\/ul>\n<ol start=\"4\">\n<li><strong>Intercellular Adhesion and Other Junctions<\/strong><\/li>\n<\/ol>\n<ul>\n<li>Several membrane-associated structures provide adhesion and communication between cells.<\/li>\n<li>Tight junctions, also called zonulae occludens, are the most apical of the junctions that form a band completely encircling each cell.<\/li>\n<li>The second type of junction is the adherens junction or zonula adherens, which also encircles the epithelial cell, usually immediately below the tight junction.<\/li>\n<li>Another anchoring junction is the desmosome or macula adherens which are disc-shaped structures at the surface of one cell that matches with identical structures at an adjacent cell surface.<\/li>\n<li>Gap junctions mediate intercellular communication rather than adhesion or occlusion between cells.<\/li>\n<\/ul>\n<ol start=\"5\">\n<li><strong>Avascular<\/strong><\/li>\n<\/ol>\n<ul>\n<li>Epithelial tissue is avascular, relying on the blood vessels of the adjacent connective tissue to bring nutrients and remove wastes.<\/li>\n<li>The exchange of substances between epithelial tissue and connective tissue occurs by diffusion.<\/li>\n<\/ul>\n<ol start=\"6\">\n<li><strong>Innervated<\/strong><\/li>\n<\/ol>\n<ul>\n<li>Epithelial tissue is innervated; that is, it has its own nerve supply.<\/li>\n<\/ul>\n<ol start=\"7\">\n<li><strong>Renew and Repair<\/strong><\/li>\n<\/ol>\n<ul>\n<li>Epithelial cells have a high rate of cell division which allows the epithelial tissue to continually renew and repair itself by sloughing off dead or injured cells and replacing them with new ones.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"functions-of-epithelial-tissue\"><\/span><strong>Functions of Epithelial Tissue<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Based on the location, epithelial tissue performs a bunch of functions. Some of which are:<\/p>\n<p><strong>Protection<\/strong><\/p>\n<ul>\n<li>One of the most critical functions of epithelial tissue is protection. It protects the cells present below against radiation, desiccation, invasion by pathogens, toxins, and physical trauma.<\/li>\n<li>The absence of blood vessels in the epithelial tissue thus prevents bleeding in the tissue during abrasion.<\/li>\n<\/ul>\n<p><strong>Transportation<\/strong><\/p>\n<ul>\n<li>Epithelial tissue also functions in the transportation of different molecules in and out of the cells with different pumps present in the epithelial tissue.<\/li>\n<li>Besides, in the <a href=\"https:\/\/microbenotes.com\/the-human-digestive-system-organs-and-functions\/\" target=\"_blank\" rel=\"noopener noreferrer\">digestive<\/a>, respiratory, and urinary system, it allows the exchange of molecules between the underlying cells and the body cavity, capillaries, and ducts.<\/li>\n<\/ul>\n<p><strong>Secretion<\/strong><\/p>\n<ul>\n<li>Glandular epithelium secretes various macromolecules like hormones responsible for multiple bodily functions.<\/li>\n<li>Many endocrine and exocrine glands also help maintain the body surfaces (skin) as well as support the functions of various organs (digestive system).<\/li>\n<\/ul>\n<p><strong>Absorption<\/strong><\/p>\n<ul>\n<li>By the function of various specialized structures like cilia and microvilli on the surface of cells, epithelial tissue also aids in the absorption of multiple molecules by increasing the surface area.<\/li>\n<li>In the digestive system, columnar cells of the small intestine help in the absorption of water and various other nutrients.<\/li>\n<\/ul>\n<p><strong>Receptor function<\/strong><\/p>\n<ul>\n<li>Some cells in the epithelial tissue are specialized to perform sensory functions that can detect the sensory information and convert them into neural signals.<\/li>\n<li>Cells in epithelial tissue like the pseudostratified columnar epithelium of the olfactory mucosa contain apical cilia that allow the sensation of odor.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"types-classification-with-examples-and-location\"><\/span><strong>Types \/ Classification with examples and location<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Epithelial tissue is divided into two types:<\/p>\n<ol>\n<li><strong>Covering and lining epithelium<\/strong>, also called the surface epithelium, that forms the outer covering of the skin and some internal organs and also forms the inner lining of blood vessels, ducts, body cavities, and the inner lining of the respiratory, digestive, urinary, and reproductive systems.<\/li>\n<li><strong>Glandular epithelium<\/strong> that makes up the secreting portion of glands such as the thyroid gland, adrenal glands, sweat glands, and digestive glands.<\/li>\n<\/ol>\n<p>Further, types of covering and lining epithelial tissue are classified according to the arrangement of cells and the shapes of those cells.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27821\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Epithelial-Tissue-Types.jpg\" alt=\"Epithelial Tissue Types\" width=\"800\" height=\"420\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Epithelial-Tissue-Types.jpg 800w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Epithelial-Tissue-Types-300x158.jpg 300w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Epithelial-Tissue-Types-768x403.jpg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<h2><span class=\"ez-toc-section\" id=\"simple-epithelium\"><\/span><strong>Simple epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Simple epithelium is made up of a single layer of identical cells, which are usually found on secretory and absorptive surfaces, where the single layer enhances these processes.<\/li>\n<li>Simple epithelium is divided into three main types, and these are named according to the shape of the cells, which differ based on their functions.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"a-simple-squamous-epithelium\"><\/span><strong>a. Simple squamous epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27811\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-squamous-epithelium.jpg\" alt=\"Simple squamous epithelium\" width=\"327\" height=\"166\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-squamous-epithelium.jpg 327w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-squamous-epithelium-300x152.jpg 300w\" sizes=\"(max-width: 327px) 100vw, 327px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>The simple squamous epithelium consists of a single layer of flat cells that resembles the tiles on a floor when viewed from the apical surface with a centrally located nucleus that is flattened and oval or spherical.<\/li>\n<li>This epithelium most commonly lines the cardiovascular and <a href=\"https:\/\/microbenotes.com\/lymphatic-system-organs\/\">lymphatic system<\/a> (<a href=\"https:\/\/microbenotes.com\/heart-anatomy-functions\/\">heart<\/a>, blood vessels, lymphatic vessels), where it is known as <strong>endothelium <\/strong>and forms the epithelial layer of serous membranes (peritoneum, pleura, pericardium), where it is called<\/li>\n<li>It is also found in air sacs of lungs, glomerular (Bowman\u2019s) capsule of kidneys, and the inner surface of the tympanic membrane (eardrum).<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"b-simple-cuboidal-epithelium\"><\/span><strong>b. Simple cuboidal epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27812\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-cuboidal-epithelium.jpg\" alt=\"Simple cuboidal epithelium\" width=\"332\" height=\"178\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-cuboidal-epithelium.jpg 332w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-cuboidal-epithelium-300x161.jpg 300w\" sizes=\"(max-width: 332px) 100vw, 332px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>Simple cuboidal epithelium is a single layer of cube-shaped cells that are round and have a centrally located nucleus.<\/li>\n<li>It covers the surface of the ovary, lines the anterior surface of the capsule of the lens of the eye, forms pigmented epithelium at the posterior surface of retina of the eye, lines kidney tubules and smaller ducts of various glands, makes up secreting portion of some glands like the thyroid gland and ducts of some glands such as the pancreas.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"c-simple-columnar-epithelium\"><\/span><strong>c. Simple columnar epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27813\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-columnar-epithelium.jpg\" alt=\"Simple columnar epithelium\" width=\"331\" height=\"285\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-columnar-epithelium.jpg 331w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Simple-columnar-epithelium-300x258.jpg 300w\" sizes=\"(max-width: 331px) 100vw, 331px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>The columnar epithelium is made by a single layer of cells, rectangular in shape, on a basement membrane.<\/li>\n<li>This epithelium lines many organs and is often derived to make it well suited for a specific function.<\/li>\n<li>Columnar epithelium lines the stomach without any surface structures. However, the free surface of the columnar epithelium lining the small intestine is covered with microvilli, which provide a vast surface area for the absorption of nutrients from the small intestine.<\/li>\n<li>In the trachea, the columnar epithelium is ciliated. Also, it contains goblet cells that secrete mucus, and in the uterine tubes, ova are propelled along by ciliary action towards the uterus.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"stratified-epithelium\"><\/span><strong>Stratified epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>A stratified epithelium consists of several layers of cells of various shapes, and basement membranes are usually absent.<\/li>\n<li>As basal cells divide, daughter cells arising from cell divisions are pushed older cells upward toward the apical layer.<\/li>\n<li>As they move toward the surface and away from blood supply in underlying connective tissue, they become dehydrated and less metabolically active.<\/li>\n<li>Tough proteins predominate as cytoplasm is reduced, and cells become tough, hard structures that eventually die.<\/li>\n<li>At the apical layer, after dead cells lose cell junctions, they are sloughed off, but they are continuously replaced as new cells emerge from basal cells.<\/li>\n<li>There are two main types of stratified epithelium: stratified squamous, stratified cuboidal, and stratified columnar epithelium.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"a-stratified-squamous-epithelium\"><\/span><strong>a. Stratified squamous epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27814\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-squamous-epithelium.jpg\" alt=\"Stratified squamous epithelium\" width=\"328\" height=\"230\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-squamous-epithelium.jpg 328w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-squamous-epithelium-300x210.jpg 300w\" sizes=\"(max-width: 328px) 100vw, 328px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<p>The stratified squamous epithelium has two or more layers of cells. The cells in the apical layer and several layers deep to it are squamous while the cells in deeper layers vary from cuboidal to columnar.<\/p>\n<p><strong>i. Keratinized stratified squamous epithelium<\/strong><\/p>\n<ul>\n<li>This epithelium develops a tough layer of keratin in the apical segment of cells and several layers deep to it<\/li>\n<li>The relative amount of keratin increases in cells as they move away from the nutritive blood supply and the organelles eventually die.<\/li>\n<li>The keratin forms a tough, relatively waterproof protective layer that prevents drying of the live cells present underneath.<\/li>\n<li>Keratinized stratified squamous epithelium forms a superficial layer of skin.<\/li>\n<\/ul>\n<p><strong>ii. Non-keratinized stratified squamous epithelium<\/strong><\/p>\n<ul>\n<li>This epithelium does not contain large amounts of keratin in the apical layer, and several layers deep and is moistened continuously by mucus from salivary and mucous glands.<\/li>\n<li>Nonkeratinized stratified squamous epithelium lines wet surfaces (lining of mouth, esophagus, part of the epiglottis, part of the pharynx, and vagina) and covers the tongue.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"b-stratified-cuboidal-epithelium\"><\/span><strong>b. Stratified cuboidal epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27815\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-cuboidal-epithelium.jpg\" alt=\"Stratified cuboidal epithelium\" width=\"328\" height=\"203\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-cuboidal-epithelium.jpg 328w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-cuboidal-epithelium-300x186.jpg 300w\" sizes=\"(max-width: 328px) 100vw, 328px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>Stratified cuboidal epithelium has multiple layers of cells in which the apical layer is made up of cuboidal cells while the deeper layer can be either cuboidal or columnar.<\/li>\n<li>Stratified cuboidal epithelium is seen in the excretory ducts of salivary and sweat glands.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"c-stratified-columnar-epithelium\"><\/span><strong>c. Stratified columnar epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27816\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-columnar-epithelium.jpg\" alt=\"Stratified columnar epithelium\" width=\"331\" height=\"303\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-columnar-epithelium.jpg 331w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Stratified-columnar-epithelium-300x275.jpg 300w\" sizes=\"(max-width: 331px) 100vw, 331px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>The stratified columnar epithelium has multiple layers of cells in which the apical layer is made up of columnar cells while the deeper layer can be either cuboidal or columnar.<\/li>\n<li>This type of epithelium is present in the conjunctiva of the eyes, parts of the urethra, and the small area in the anal mucosa.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"pseudostratified-columnar-epithelium\"><\/span><strong>Pseudostratified columnar epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27818\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Pseudostratified-columnar-epithelium.jpg\" alt=\"Pseudostratified columnar epithelium\" width=\"345\" height=\"278\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Pseudostratified-columnar-epithelium.jpg 345w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Pseudostratified-columnar-epithelium-300x242.jpg 300w\" sizes=\"(max-width: 345px) 100vw, 345px\" \/><\/p>\n<p>Image Source: <a href=\"https:\/\/openstax.org\/books\/anatomy-and-physiology\/pages\/4-2-epithelial-tissue\" target=\"_blank\" rel=\"noopener noreferrer\">Rice University (OpenStax)<\/a><\/p>\n<ul>\n<li>Pseudostratified epithelium appears to have several layers because the nuclei of the cells are present at various levels.<\/li>\n<li>Although all the cells are attached to the basement membrane in a single layer, some cells do not reach the apical surface.<\/li>\n<li>As a result of these features, it appears as a multilayered tissue, but in fact, is the simple epithelium.<\/li>\n<li>This epithelium lines epididymis, larger ducts of many glands, and parts of male urethra and airways of most of the upper respiratory tract.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"transitional-epithelium-tissue\"><\/span><strong>Transitional epithelium tissue<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27820\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Transitional-epithelium-tissue.png\" alt=\"Transitional epithelium tissue\" width=\"323\" height=\"215\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Transitional-epithelium-tissue.png 323w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Transitional-epithelium-tissue-300x200.png 300w\" sizes=\"(max-width: 323px) 100vw, 323px\" \/><\/p>\n<p>Figure: Transitional epithelium tissue. Image Source: <a href=\"https:\/\/en.wikipedia.org\/wiki\/Transitional_epithelium#\/media\/File:Illu_transitional_epithelium.svg\" target=\"_blank\" rel=\"noopener noreferrer\">Wikipedia<\/a>.<\/p>\n<ul>\n<li>Transitional epithelium (urothelium) has a variable appearance (transitional).<\/li>\n<li>In a relaxed or unstretched state, looks like stratified cuboidal epithelium, except apical layer cells tend to be broad and rounded.<\/li>\n<li>As tissue is stretched, cells become flatter, giving the appearance of stratified squamous epithelium. Multiple layers and elasticity make it ideal for lining hollow structures (urinary bladder) subject to expansion from within.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"glandular-epithelium\"><\/span><strong>Glandular Epithelium<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Epithelial cells that function mainly to produce and secrete various macromolecules may occur in epithelia with other significant functions or comprise specialized organs called glands.<\/li>\n<li>Scattered secretory cells, sometimes called unicellular glands, are common in simple cuboidal, simple columnar, and pseudostratified epithelia.<\/li>\n<li>Glands develop from covering epithelia in the fetus by cell proliferation and growth into the underlying connective tissue, followed by further differentiation.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-27810\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Glandular-Epithelium.png\" alt=\"Glandular Epithelium\" width=\"550\" height=\"471\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Glandular-Epithelium.png 550w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Glandular-Epithelium-300x257.png 300w\" sizes=\"(max-width: 550px) 100vw, 550px\" \/><\/p>\n<p>Figure: Main types of glands. Glands differentiate from epithelial tissues during embryo development. Arrows point to the released substances. Image Source: <a href=\"https:\/\/mmegias.webs.uvigo.es\/02-english\/guiada_a_glandular.php\" target=\"_blank\" rel=\"noopener noreferrer\">University of Vigo<\/a>.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"endocrine-glands\"><\/span><strong>Endocrine glands <\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li>The secretions of endocrine glands, called hormones, enter the interstitial fluid and then diffuse into the bloodstream without flowing through a duct.<\/li>\n<li>Endocrine secretions have far-reaching effects because they are distributed throughout the body by the bloodstream.<\/li>\n<li>Examples of endocrine glands include pituitary gland at the base of the brain, the pineal gland in the brain, thyroid and parathyroid glands near larynx (voice box), adrenal glands superior to kidneys, pancreas near the stomach, ovaries in the pelvic cavity, testes in the scrotum, thymus in the thoracic cavity.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"exocrine-glands\"><\/span><strong>Exocrine glands<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li>Exocrine glands secrete their products into ducts that release the secretions onto the surface of organs such as the skin surface or the lumen of a hollow organ.<\/li>\n<li>The effects of exocrine gland secretions are limited, and some of them would be harmful if they entered the bloodstream.<\/li>\n<li>Sweat, oil, and earwax glands of the skin, digestive glands such as salivary glands (secrete into mouth cavity) and pancreas (secretes into the small intestine) are the examples of exocrine glands.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"references\"><\/span><strong>References<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Mescher AL (2016). Basic Histology. Fourteenth Edition. McGraw-Hill Education.<\/li>\n<li>Tortora GJ and Derrickson B (2017). Principles of Physiology and Anatomy. Fifteenth Edition. John Wiley &amp; Sons, Inc.<\/li>\n<li>Waugh A and Grant A. (2004) Anatomy and Physiology. Ninth Edition. Churchill Livingstone.<\/li>\n<li>https:\/\/www.kenhub.com\/en\/library\/anatomy\/overview-and-types-of-epithelial-tissue<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"internet-sources\"><\/span>Internet Sources<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>3% &#8211; https:\/\/quizlet.com\/25768290\/chapter-3-tissues-flash-cards\/<\/li>\n<li>2% &#8211; https:\/\/quizlet.com\/47458913\/chapter-4-flash-cards\/<\/li>\n<li>2% &#8211; https:\/\/quizlet.com\/26692499\/chapt-4-epithelial-tissue-flash-cards\/<\/li>\n<li>2% &#8211; https:\/\/quizlet.com\/25669314\/anatomy-ch-4-reading-flash-cards\/<\/li>\n<li>2% &#8211; https:\/\/doctor2017.jumedicine.com\/wp-content\/uploads\/sites\/7\/2018\/01\/Surface-epithelium.pdf<\/li>\n<li>1% &#8211; https:\/\/www.youtube.com\/watch?v=0NEV-Rd7OgA<\/li>\n<li>1% &#8211; https:\/\/www.thoughtco.com\/animal-anatomy-epithelial-tissue-373206<\/li>\n<li>1% &#8211; https:\/\/www.thenursepage.com\/epithelial-tissues-types-of-epithelial-tissues\/<\/li>\n<li>1% &#8211; https:\/\/www.cram.com\/flashcards\/ap-i-ch4-6264721<\/li>\n<li>1% &#8211; https:\/\/www.coursehero.com\/file\/p5d8jsc\/Epithelial-tissue-may-be-divided-into-two-types-1-Covering-and-lining\/<\/li>\n<li>1% &#8211; https:\/\/study.com\/academy\/lesson\/simple-cuboidal-epithelium-location-structure-function.html<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/gb\/340412792\/histology-epithelia-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/ca\/310892532\/chapter-4-bio-235-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/95543301\/epithelial-tissue-covering-and-lining-epithelium-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/72533810\/anatomy-and-physiology-tissue-level-of-organization-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/6320460\/anatom-ch3-terms2-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/50190298\/44-epithelial-tissue-quiz-1-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/326765543\/apchapter-4-the-tissue-level-of-organization-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/26142932\/anatomy-lecture-3-tissues-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/25583191\/anatomy-ch-4-epithelial-tissue-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/225671385\/final-exam-specific-objectives-chapter-4-tissues-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/211826315\/chapter-4-the-tissue-level-of-organization-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/20156045\/the-tissue-level-of-organisation-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/17285188\/biomed-module-7-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/14302876\/epithelial-tissues-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/quizlet.com\/13823304\/classification-of-tissues-part-1-flash-cards\/<\/li>\n<li>1% &#8211; https:\/\/healthjade.net\/basement-membrane\/<\/li>\n<li>1% &#8211; https:\/\/doctor2019.jumedicine.com\/wp-content\/uploads\/sites\/10\/2020\/01\/Glandular-Epithelium.pdf.pdf<\/li>\n<li>&lt;1% &#8211; https:\/\/www.studymode.com\/essays\/Outline-The-Structure-Of-The-Main-1455732.html<\/li>\n<li>&lt;1% &#8211; https:\/\/www.lab.anhb.uwa.edu.au\/mb140\/CorePages\/Epithelia\/epithel.htm<\/li>\n<li>&lt;1% &#8211; https:\/\/www.kenhub.com\/en\/library\/anatomy\/overview-and-types-of-epithelial-tissue<\/li>\n<li>&lt;1% &#8211; https:\/\/www.differencebetween.com\/difference-between-simple-stratified-and-pseudostratified-epithelial-tissue\/<\/li>\n<li>&lt;1% &#8211; https:\/\/www.coursehero.com\/file\/p502iic\/630x-LM-Mark-Nielsen-Sectional-view-of-keratinized-stratified-squamous\/<\/li>\n<li>&lt;1% &#8211; https:\/\/www.britannica.com\/science\/microvilli<\/li>\n<li>&lt;1% &#8211; https:\/\/quizlet.com\/99144165\/epithelium-tissue-functions-and-locations-flash-cards\/<\/li>\n<li>&lt;1% &#8211; https:\/\/quizlet.com\/9814963\/chapter-5-tissues-flash-cards\/<\/li>\n<li>&lt;1% &#8211; https:\/\/quizlet.com\/24665603\/body-tissues-flash-cards\/<\/li>\n<li>&lt;1% &#8211; https:\/\/quizlet.com\/18641983\/chapter-3-cells-and-tissues-flash-cards\/<\/li>\n<li>&lt;1% &#8211; https:\/\/oerpub.github.io\/epubjs-demo-book\/content\/m46048.xhtml<\/li>\n<li>&lt;1% &#8211; https:\/\/micro.magnet.fsu.edu\/primer\/anatomy\/brightfieldgallery\/index.html<\/li>\n<li>&lt;1% &#8211; https:\/\/en.wikipedia.org\/wiki\/Stratified_cuboidal_epithelium<\/li>\n<li>&lt;1% &#8211; https:\/\/en.m.wikipedia.org\/wiki\/Urethra<\/li>\n<li>&lt;1% &#8211; https:\/\/courses.lumenlearning.com\/boundless-ap\/chapter\/epithelial-tissue\/<\/li>\n<li>&lt;1% &#8211; https:\/\/courses.lumenlearning.com\/boundless-ap\/chapter\/absorption\/<\/li>\n<li>&lt;1% &#8211; https:\/\/anatomyandphysiologyi.com\/epithelial-tissue\/<\/li>\n<li>&lt;1% &#8211; http:\/\/www.histology.leeds.ac.uk\/tissue_types\/epithelia\/epi_specialisations.php<\/li>\n<li>&lt;1% &#8211; http:\/\/www.differencebetween.net\/science\/health\/difference-between-exocrine-and-endocrine\/<\/li>\n<li>&lt;1% &#8211; http:\/\/medcell.med.yale.edu\/systems_cell_biology\/epithelium_lab.php<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Epithelial Tissue definition Epithelial Tissue is one of the four types of tissue (epithelial, muscular, connective, and nervous) in animals which consists of closely aggregated polyhedral cells adhering firmly to &#8230; <a title=\"Epithelial Tissue &#8211; Definition, types, functions, examples\" class=\"read-more\" href=\"https:\/\/microbenotes.com\/epithelial-tissue\/\" aria-label=\"Read more about Epithelial Tissue &#8211; Definition, types, functions, examples\">Read more<\/a><\/p>\n","protected":false},"author":11,"featured_media":27821,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6189],"tags":[5335,5344,5345,5336],"custom":{"td_video":"","featured_image":"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/05\/Epithelial-Tissue-Types.jpg","author":{"name":"Anupama Sapkota","avatar":"https:\/\/secure.gravatar.com\/avatar\/0e9c86afc1670c49efeb260138ec905b?s=96&d=mm&r=g"},"categories":[{"term_id":6189,"name":"Biology","slug":"biology","term_group":0,"term_taxonomy_id":6189,"taxonomy":"category","description":"<strong>Biology is a vast discipline that deals with the study of living beings and their vital processes, that deal with the physicochemical aspects of life.<\/strong>\r\n\r\nBiology is a natural science that utilizes different structural and functional concepts for the differentiation of living beings from non-living beings.\r\nAt present times, as a result of cross-disciplinary research, other disciplines like chemistry, physics, computer science, and medicine have been integrated with biology, resulting in areas like biochemistry, biophysics, biomedicine, and bioinformatics.\r\nBiology is further divided into separate branches for the convenience of study, even though all of these branches are interrelated to one another.\r\nBiology is separated into botany (the study of plants) and zoology (the study of animals), morphology (structure), and physiology (function).\r\nLiving beings have been divided into different kingdoms, phylum, classes, orders, and genus to make the identification and studies related to different organisms more feasible.\r\nTraditionally, biology was only associated with the structure and function of living beings.\r\nWith time, however, biology deals with the fundamental levels of life, resulting in a separate discipline termed, molecular biology.\r\nBiology has now been developed into modern biology which is based on certain foundations like cell theory, evolution, genetics, homeostasis, and chemical energy.\r\nBiology defines cell as the fundamental unit of life, which is common in all living beings, microscopic, and macroscopic.\r\nBesides, other concepts like evolution and genomics further help in understanding the origin, evolution, and relationship among living beings.\r\nGenetics is another component of biology that helps in the differentiation of living beings based on their genomic composition.\r\nHomeostasis is another crucial unit of biology which suggests that all living organisms maintain a constant internal environment.\r\nNon-living parts of the world like the air, water, and soil have been closely related to the living world, which creates a close relationship between biology and the environment.\r\n\r\n<strong>Developmental biology is a branch of natural science that studies various interactions involved in the formation of the heterogeneous shape, structure, and size of different organisms that occur during the development of an embryo into an adult.<\/strong>\r\n<ul>\r\n \t<li>In short, developmental biology is a discipline that deals with the processes involved in the development of a multicellular organism as controlled by genetic information.<\/li>\r\n \t<li>Developmental biology studies the mechanisms of development, differentiation, and growth in plants and animals at the cellular, molecular, genetic, and evolutionary levels.<\/li>\r\n \t<li>Different forms of reproduction like sexual reproduction, asexual reproduction, metamorphosis, and germination of seeds and embryos are essential aspects of developmental biology.<\/li>\r\n \t<li>Developmental biology is a fast-growing discipline that is interrelated with a vast array of disciplines like molecular biology, anatomy, cancer biology, immunology, ecology, evolutionary biology, cell biology, and physiology.<\/li>\r\n \t<li>Studies done in developmental biology have provided information on the molecular genetics of development, growth factors, oncogenes, the evolution of developmental control, mechanisms of differentiation, gametogenesis, fertilization, and control of gene expression.<\/li>\r\n \t<li>Other areas of emphasis in developmental biology include transcriptional control, cell-cell interactions, regulatory hierarchies, signal transduction, etc.<\/li>\r\n \t<li>The development of developmental biology as an important discipline is due to its applications in different areas.<\/li>\r\n \t<li>The results of the research are used in fertility clinics where the information is used for artificial insemination, test-tube culture, and to treat other infertility issues.<\/li>\r\n \t<li>Tissue engineering is another essential technique that utilizes concepts of developmental biology to grow replacement tissues in plastic dishes and to control the formation of cancer cells.<\/li>\r\n \t<li>Reactivation of stem cells to grow replacement tissues is also by virtue of accomplishments made in developmental biology.<\/li>\r\n \t<li>In agriculture, techniques developed for selective breeding by optimizing root systems, plant size, and flowering time has allowed for a better and increased harvest.<\/li>\r\n<\/ul>\r\n<strong>Cancer biology is a branch of biology that studies the complex expression of genes, proteins, and biological processes that initiated the development and growth of\u00a0cancers.<\/strong>\r\n<ul>\r\n \t<li>Understanding the many different biological systems underlying cancer\u2019s development is essential for understanding cancer and identifying new targets for treatment.<\/li>\r\n \t<li>Most of the researches in cancer biology are concerned with genomic conservation; in particular, how the genetic composition of cell ensure that no errors occur during processes like copying the genome or repairing it after damage.<\/li>\r\n \t<li>The genetic conservation also ensures that a complete copy of the genome is inherited by each daughter cell.<\/li>\r\n \t<li>Cancer results when one or all of these processes go wrong, which leads to inconsistency in cancer cells that can successfully be exploited for treatment.<\/li>\r\n \t<li>Another critical aspect of cancer biology is studies related to protein function and interactions on a systems-wide scale to identify how signaling pathways are restructured in cancer cells, and how this affects cell behavior, cell shape, and cell metabolism.<\/li>\r\n \t<li>Cancer cells are transformed cells after acquiring a series of changes that permit them to form tumors, which behave differently depending on the genetic changes that result in this transformation.<\/li>\r\n \t<li>The hallmarks of cancer cells include signs like self-sufficiency in growth signals, evasion of programmed cell death, insensitivity to growth-inhibitory signals, limitless replicative potential, sustained angiogenesis, and tissue invasion.<\/li>\r\n \t<li>Cancer biology is a vast branch that studies the process of carcinogenesis, mutations, carcinogens, and cellular changes.<\/li>\r\n \t<li>The role of cancer biology in the perioperative period is of increasing interest as it provides evidence regarding fundamental principles of cancer biology, especially tumor microenvironment, and discusses new therapeutic opportunities.<\/li>\r\n \t<li>Different researches in cancer biology help in the identification of cancer symptoms and the formation of malignant tumors of different cells found in living beings.<\/li>\r\n \t<li>These researches also enable the differentiation between normal cells and cancer cells which assists in the early diagnosis of cancer.<\/li>\r\n<\/ul>","parent":0,"count":195,"filter":"raw","cat_ID":6189,"category_count":195,"category_description":"<strong>Biology is a vast discipline that deals with the study of living beings and their vital processes, that deal with the physicochemical aspects of life.<\/strong>\r\n\r\nBiology is a natural science that utilizes different structural and functional concepts for the differentiation of living beings from non-living beings.\r\nAt present times, as a result of cross-disciplinary research, other disciplines like chemistry, physics, computer science, and medicine have been integrated with biology, resulting in areas like biochemistry, biophysics, biomedicine, and bioinformatics.\r\nBiology is further divided into separate branches for the convenience of study, even though all of these branches are interrelated to one another.\r\nBiology is separated into botany (the study of plants) and zoology (the study of animals), morphology (structure), and physiology (function).\r\nLiving beings have been divided into different kingdoms, phylum, classes, orders, and genus to make the identification and studies related to different organisms more feasible.\r\nTraditionally, biology was only associated with the structure and function of living beings.\r\nWith time, however, biology deals with the fundamental levels of life, resulting in a separate discipline termed, molecular biology.\r\nBiology has now been developed into modern biology which is based on certain foundations like cell theory, evolution, genetics, homeostasis, and chemical energy.\r\nBiology defines cell as the fundamental unit of life, which is common in all living beings, microscopic, and macroscopic.\r\nBesides, other concepts like evolution and genomics further help in understanding the origin, evolution, and relationship among living beings.\r\nGenetics is another component of biology that helps in the differentiation of living beings based on their genomic composition.\r\nHomeostasis is another crucial unit of biology which suggests that all living organisms maintain a constant internal environment.\r\nNon-living parts of the world like the air, water, and soil have been closely related to the living world, which creates a close relationship between biology and the environment.\r\n\r\n<strong>Developmental biology is a branch of natural science that studies various interactions involved in the formation of the heterogeneous shape, structure, and size of different organisms that occur during the development of an embryo into an adult.<\/strong>\r\n<ul>\r\n \t<li>In short, developmental biology is a discipline that deals with the processes involved in the development of a multicellular organism as controlled by genetic information.<\/li>\r\n \t<li>Developmental biology studies the mechanisms of development, differentiation, and growth in plants and animals at the cellular, molecular, genetic, and evolutionary levels.<\/li>\r\n \t<li>Different forms of reproduction like sexual reproduction, asexual reproduction, metamorphosis, and germination of seeds and embryos are essential aspects of developmental biology.<\/li>\r\n \t<li>Developmental biology is a fast-growing discipline that is interrelated with a vast array of disciplines like molecular biology, anatomy, cancer biology, immunology, ecology, evolutionary biology, cell biology, and physiology.<\/li>\r\n \t<li>Studies done in developmental biology have provided information on the molecular genetics of development, growth factors, oncogenes, the evolution of developmental control, mechanisms of differentiation, gametogenesis, fertilization, and control of gene expression.<\/li>\r\n \t<li>Other areas of emphasis in developmental biology include transcriptional control, cell-cell interactions, regulatory hierarchies, signal transduction, etc.<\/li>\r\n \t<li>The development of developmental biology as an important discipline is due to its applications in different areas.<\/li>\r\n \t<li>The results of the research are used in fertility clinics where the information is used for artificial insemination, test-tube culture, and to treat other infertility issues.<\/li>\r\n \t<li>Tissue engineering is another essential technique that utilizes concepts of developmental biology to grow replacement tissues in plastic dishes and to control the formation of cancer cells.<\/li>\r\n \t<li>Reactivation of stem cells to grow replacement tissues is also by virtue of accomplishments made in developmental biology.<\/li>\r\n \t<li>In agriculture, techniques developed for selective breeding by optimizing root systems, plant size, and flowering time has allowed for a better and increased harvest.<\/li>\r\n<\/ul>\r\n<strong>Cancer biology is a branch of biology that studies the complex expression of genes, proteins, and biological processes that initiated the development and growth of\u00a0cancers.<\/strong>\r\n<ul>\r\n \t<li>Understanding the many different biological systems underlying cancer\u2019s development is essential for understanding cancer and identifying new targets for treatment.<\/li>\r\n \t<li>Most of the researches in cancer biology are concerned with genomic conservation; in particular, how the genetic composition of cell ensure that no errors occur during processes like copying the genome or repairing it after damage.<\/li>\r\n \t<li>The genetic conservation also ensures that a complete copy of the genome is inherited by each daughter cell.<\/li>\r\n \t<li>Cancer results when one or all of these processes go wrong, which leads to inconsistency in cancer cells that can successfully be exploited for treatment.<\/li>\r\n \t<li>Another critical aspect of cancer biology is studies related to protein function and interactions on a systems-wide scale to identify how signaling pathways are restructured in cancer cells, and how this affects cell behavior, cell shape, and cell metabolism.<\/li>\r\n \t<li>Cancer cells are transformed cells after acquiring a series of changes that permit them to form tumors, which behave differently depending on the genetic changes that result in this transformation.<\/li>\r\n \t<li>The hallmarks of cancer cells include signs like self-sufficiency in growth signals, evasion of programmed cell death, insensitivity to growth-inhibitory signals, limitless replicative potential, sustained angiogenesis, and tissue invasion.<\/li>\r\n \t<li>Cancer biology is a vast branch that studies the process of carcinogenesis, mutations, carcinogens, and cellular changes.<\/li>\r\n \t<li>The role of cancer biology in the perioperative period is of increasing interest as it provides evidence regarding fundamental principles of cancer biology, especially tumor microenvironment, and discusses new therapeutic opportunities.<\/li>\r\n \t<li>Different researches in cancer biology help in the identification of cancer symptoms and the formation of malignant tumors of different cells found in living beings.<\/li>\r\n \t<li>These researches also enable the differentiation between normal cells and cancer cells which assists in the early diagnosis of cancer.<\/li>\r\n<\/ul>","cat_name":"Biology","category_nicename":"biology","category_parent":0}]},"_links":{"self":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41078"}],"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\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/comments?post=41078"}],"version-history":[{"count":0,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41078\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media\/27821"}],"wp:attachment":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media?parent=41078"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/categories?post=41078"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/tags?post=41078"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}