{"id":185546,"date":"2025-01-22T17:40:35","date_gmt":"2025-01-22T17:40:35","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=185546"},"modified":"2025-01-22T17:40:37","modified_gmt":"2025-01-22T17:40:37","slug":"which-is-incorrect-about-the-fc-region-of-an-immunoglobulin","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/01\/22\/which-is-incorrect-about-the-fc-region-of-an-immunoglobulin\/","title":{"rendered":"Which is incorrect about the FC region of an immunoglobulin"},"content":{"rendered":"\n<p>Which is incorrect about the FC region of an immunoglobulin?<\/p>\n\n\n\n<p>It forms an antigen binding site<\/p>\n\n\n\n<p>It is called the crystallizable fragment<\/p>\n\n\n\n<p>It determines the class to which the immunoglobulin belongs<\/p>\n\n\n\n<p>It contains an infector molecule that combined cells such as macrophages and mast cells<\/p>\n\n\n\n<p>It contains an effector molecule that can fix complement<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\">The correct answer and explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Correct Answer: It forms an antigen-binding site<\/strong><\/p>\n\n\n\n<p><strong>Explanation:<\/strong><\/p>\n\n\n\n<p>The <strong>Fc region<\/strong> of an immunoglobulin (antibody) does not form an antigen-binding site. Instead, the antigen-binding sites are located in the <strong>Fab (Fragment antigen-binding)<\/strong> regions of the antibody. These Fab regions consist of the variable domains of the heavy and light chains, which are specifically structured to recognize and bind to a unique antigen.<\/p>\n\n\n\n<p>The Fc region, on the other hand, is the constant portion of the antibody molecule. Its primary roles are not related to antigen recognition but to mediating immune system interactions and determining the antibody&#8217;s effector functions. The term &#8220;Fc&#8221; stands for &#8220;Fragment crystallizable,&#8221; reflecting its ability to form crystals during certain experimental conditions. This region determines the <strong>class (or isotype) of the immunoglobulin<\/strong>, such as IgG, IgA, IgE, IgM, or IgD, and influences its interaction with other components of the immune system.<\/p>\n\n\n\n<p>Functions of the Fc region include:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Effector Function:<\/strong> The Fc region can bind to Fc receptors on immune cells such as macrophages, mast cells, and natural killer (NK) cells, triggering various immune responses such as phagocytosis or degranulation.<\/li>\n\n\n\n<li><strong>Complement Activation:<\/strong> In certain classes of immunoglobulins (e.g., IgG and IgM), the Fc region can interact with complement proteins to initiate the complement cascade, a critical mechanism for pathogen destruction.<\/li>\n<\/ol>\n\n\n\n<p>The incorrect statement\u2014&#8221;It forms an antigen-binding site&#8221;\u2014confuses the function of the Fc region with that of the Fab region. Understanding the distinct roles of the Fab and Fc regions is crucial for comprehending antibody structure and function in the immune response. This knowledge is especially important in immunology and the design of therapeutic antibodies.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Which is incorrect about the FC region of an immunoglobulin? It forms an antigen binding site It is called the crystallizable fragment It determines the class to which the immunoglobulin belongs It contains an infector molecule that combined cells such as macrophages and mast cells It contains an effector molecule that can fix complement The [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-185546","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/185546","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=185546"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/185546\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=185546"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=185546"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=185546"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}