{"id":206445,"date":"2025-03-29T10:26:42","date_gmt":"2025-03-29T10:26:42","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=206445"},"modified":"2025-03-29T10:26:45","modified_gmt":"2025-03-29T10:26:45","slug":"the-oxygen-atom-in-urea-comes-from-a-water-molecule-that-participates-in-a-hydrolysis-reaction","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/29\/the-oxygen-atom-in-urea-comes-from-a-water-molecule-that-participates-in-a-hydrolysis-reaction\/","title":{"rendered":"The oxygen atom in urea comes from a water molecule that participates in a hydrolysis reaction"},"content":{"rendered":"\n

The oxygen atom in urea comes from a water molecule that participates in a hydrolysis reaction.<\/p>\n\n\n\n

a.All three statements are true.<\/p>\n\n\n\n

b.Two of the three statements are true.<\/p>\n\n\n\n

c.Only one of the statements is true.<\/p>\n\n\n\n

d.None of the statements is true.<\/p>\n\n\n\n

The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n

Correct Answer: (C) Only one of the statements is true.<\/strong><\/h3>\n\n\n\n

Explanation:<\/strong><\/h3>\n\n\n\n

Urea (CO(NH\u2082)\u2082<\/strong>) is a significant nitrogenous waste product formed primarily in the liver through the urea cycle (or ornithine cycle)<\/strong>. The question states that the oxygen atom in urea originates from a water molecule that participates in a hydrolysis reaction<\/strong>. To determine the validity of this claim, let\u2019s analyze how urea is synthesized.<\/p>\n\n\n\n

    \n
  1. Synthesis of Urea:<\/strong><\/li>\n<\/ol>\n\n\n\n
      \n
    • Urea is formed in the liver during the urea cycle.<\/li>\n\n\n\n
    • The key precursor to urea is carbamoyl phosphate<\/strong>, which is synthesized from ammonia (NH\u2083), bicarbonate (HCO\u2083\u207b), and ATP<\/strong>.<\/li>\n\n\n\n
    • The oxygen atom in urea comes from the bicarbonate ion (HCO\u2083\u207b)<\/strong>, not from a water molecule.<\/li>\n\n\n\n
    • Therefore, the statement that the oxygen atom in urea comes from water<\/strong> is false.<\/li>\n<\/ul>\n\n\n\n
        \n
      1. Role of Hydrolysis in Urea Formation:<\/strong><\/li>\n<\/ol>\n\n\n\n
          \n
        • While hydrolysis reactions are involved in argininosuccinate cleavage<\/strong> and arginine hydrolysis<\/strong>, these reactions do not contribute the oxygen atom in urea.<\/li>\n\n\n\n
        • Instead, the final step of the urea cycle involves the enzyme arginase<\/strong>, which hydrolyzes arginine to produce urea and ornithine<\/strong>. This reaction requires water<\/strong>, but water does not donate the oxygen atom in urea.<\/li>\n<\/ul>\n\n\n\n
            \n
          1. Evaluating the Answer Choices:<\/strong><\/li>\n<\/ol>\n\n\n\n
              \n
            • The statement that the oxygen atom in urea originates from water is incorrect<\/strong>.<\/li>\n\n\n\n
            • Since only this statement is being evaluated, and it is false, only one of the statements is true<\/strong>, making option (C) the correct choice<\/strong>.<\/li>\n<\/ul>\n\n\n\n

              Thus, the oxygen in urea originates from bicarbonate (HCO\u2083\u207b)<\/strong>, not water, refuting the claim in the question.<\/p>\n\n\n\n

              \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

              The oxygen atom in urea comes from a water molecule that participates in a hydrolysis reaction. a.All three statements are true. b.Two of the three statements are true. c.Only one of the statements is true. d.None of the statements is true. The correct answer and explanation is : Correct Answer: (C) Only one of the […]<\/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-206445","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206445","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=206445"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206445\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=206445"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=206445"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=206445"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}