{"id":219329,"date":"2025-05-26T03:52:29","date_gmt":"2025-05-26T03:52:29","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=219329"},"modified":"2025-05-26T03:52:31","modified_gmt":"2025-05-26T03:52:31","slug":"what-is-the-primary-role-of-oxygen-in-cellular-respiration","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/26\/what-is-the-primary-role-of-oxygen-in-cellular-respiration\/","title":{"rendered":"What Is The Primary Role Of Oxygen In Cellular Respiration"},"content":{"rendered":"\n

What Is The Primary Role Of Oxygen In Cellular Respiration? To Act As An Acceptor For Electrons And Hydrogen Resulting In Formation Of Water. To Yield Energy In The Form Of ATP As It Is Passed Down The Respiratory Chain To Combine With Lactate, Forming Pyruvate. To Catalyze The Reactions Of Glycolysis To Combine With Carbon, Forming CO2.<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

Correct Answer:<\/strong> Photorespiration<\/strong><\/p>\n\n\n\n

\n\n\n\n

Explanation<\/h3>\n\n\n\n

In C3 plants<\/strong>, the conservation of water often leads to photorespiration<\/strong>, a process that is generally wasteful for the plant. This occurs primarily due to the closure of stomata<\/strong> under hot and dry conditions, which plants do to reduce water loss through transpiration.<\/p>\n\n\n\n

Stomata are tiny openings on the leaves that allow for gas exchange\u2014CO\u2082 enters<\/strong>, and O\u2082 and water vapor exit<\/strong>. When the plant experiences water stress, it closes its stomata to conserve moisture. However, this also limits the intake of carbon dioxide (CO\u2082)<\/strong>, which is essential for the Calvin cycle<\/strong> in photosynthesis.<\/p>\n\n\n\n

As CO\u2082 becomes limited inside the leaf, the concentration of oxygen (O\u2082)<\/strong> increases because it continues to be produced during the light-dependent reactions of photosynthesis. The enzyme RuBisCO<\/strong>, which normally fixes CO\u2082 to start the Calvin cycle, starts binding O\u2082 instead of CO\u2082<\/strong> due to the higher oxygen concentration. This alternative pathway is known as photorespiration<\/strong>.<\/p>\n\n\n\n

Unlike normal photosynthesis, photorespiration does not produce sugars<\/strong>. Instead, it uses energy and releases CO\u2082<\/strong>, making it a counterproductive process for the plant. It is considered a metabolic flaw<\/strong> in C3 plants, particularly under stress conditions like drought or high temperatures.<\/p>\n\n\n\n

C3 plants, named for the 3-carbon compound (3-phosphoglycerate) formed during the first step of the Calvin cycle, are the most common type of plants. However, under conditions favoring photorespiration, they become less efficient.<\/p>\n\n\n\n

This is one of the reasons C4 plants<\/strong> evolved. They have a specialized mechanism to minimize photorespiration by spatially separating the initial CO\u2082 fixation and the Calvin cycle, thus maintaining high CO\u2082 levels around RuBisCO.<\/p>\n\n\n\n

In summary, when water conservation leads to stomatal closure in C3 plants, photorespiration is promoted<\/strong> due to reduced CO\u2082 and increased O\u2082 inside the leaf, making this the correct answer.<\/p>\n\n\n\n

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

What Is The Primary Role Of Oxygen In Cellular Respiration? To Act As An Acceptor For Electrons And Hydrogen Resulting In Formation Of Water. To Yield Energy In The Form Of ATP As It Is Passed Down The Respiratory Chain To Combine With Lactate, Forming Pyruvate. To Catalyze The Reactions Of Glycolysis To Combine With […]<\/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-219329","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/219329","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=219329"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/219329\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=219329"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=219329"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=219329"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}