{"id":213985,"date":"2025-05-13T08:54:02","date_gmt":"2025-05-13T08:54:02","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=213985"},"modified":"2025-05-13T08:54:04","modified_gmt":"2025-05-13T08:54:04","slug":"consider-the-biochemical-pathway","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/13\/consider-the-biochemical-pathway\/","title":{"rendered":"Consider the biochemical pathway"},"content":{"rendered":"\n<p>Consider the biochemical pathway: A-E1?B-E2?C. If Enzyme 2 is inactive, which of the following compounds will accumulate?<\/p>\n\n\n\n<p>Consider the biochemical pathway: A-E1?B-E2?C<\/p>\n\n\n\n<p>If Enzyme 2 is inactive, which of the following compounds will accumulate?<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Correct Answer:<\/strong> <strong>B<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Explanation:<\/strong><\/h3>\n\n\n\n<p>In biochemical pathways, compounds are converted from one form to another through <strong>enzymatic reactions<\/strong>, each step being catalyzed by a specific <strong>enzyme<\/strong>. Let&#8217;s break down the given pathway:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>A --(E1)--&gt; B --(E2)--&gt; C<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>E1 (Enzyme 1)<\/strong> catalyzes the conversion of <strong>A to B<\/strong>.<\/li>\n\n\n\n<li><strong>E2 (Enzyme 2)<\/strong> catalyzes the conversion of <strong>B to C<\/strong>.<\/li>\n<\/ul>\n\n\n\n<p>Now, the question states that <strong>Enzyme 2 is inactive<\/strong>. This means that <strong>E2 is not functioning<\/strong>, and therefore, it <strong>cannot convert B into C<\/strong>. However, <strong>Enzyme 1 is still active<\/strong>, so it will continue to convert <strong>A into B<\/strong>.<\/p>\n\n\n\n<p>Because <strong>B cannot be processed further into C<\/strong>, <strong>B will accumulate<\/strong> over time. This is a common principle in metabolic biochemistry where a block at a certain enzymatic step leads to a <strong>buildup of the substrate<\/strong> for that reaction.<\/p>\n\n\n\n<p>Let\u2019s consider the roles of each compound:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>A<\/strong>: The starting molecule; it is converted to B by E1.<\/li>\n\n\n\n<li><strong>B<\/strong>: The intermediate product; it <strong>accumulates<\/strong> because E2 is inactive.<\/li>\n\n\n\n<li><strong>C<\/strong>: The final product; its synthesis is <strong>blocked<\/strong> because E2 is inactive.<\/li>\n<\/ul>\n\n\n\n<p>This type of pathway regulation is not only theoretical but has practical implications. In <strong>inborn errors of metabolism<\/strong>, for example, a genetic defect in an enzyme leads to accumulation of a substrate, which can be toxic or interfere with other processes. For example, in <strong>phenylketonuria (PKU)<\/strong>, a deficiency in the enzyme that converts phenylalanine to tyrosine leads to the accumulation of phenylalanine.<\/p>\n\n\n\n<p>In summary, when an enzyme in a biochemical pathway is nonfunctional, the <strong>compound just before the block<\/strong> accumulates, because it is produced by the preceding step but cannot proceed further. Therefore, the correct answer is <strong>B<\/strong>, as it is the substrate for the inactive enzyme (E2).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Consider the biochemical pathway: A-E1?B-E2?C. If Enzyme 2 is inactive, which of the following compounds will accumulate? Consider the biochemical pathway: A-E1?B-E2?C If Enzyme 2 is inactive, which of the following compounds will accumulate? The Correct Answer and Explanation is: Correct Answer: B Explanation: In biochemical pathways, compounds are converted from one form to another [&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-213985","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/213985","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=213985"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/213985\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=213985"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=213985"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=213985"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}