{"id":130,"date":"2012-11-05T11:37:57","date_gmt":"2012-11-05T15:37:57","guid":{"rendered":"https:\/\/sites.owu.edu\/wolverton\/?page_id=130"},"modified":"2016-12-01T08:50:42","modified_gmt":"2016-12-01T13:50:42","slug":"regulation-of-respiration","status":"publish","type":"page","link":"https:\/\/sites.owu.edu\/wolverton\/teaching\/cell-bio\/regulation-of-respiration\/","title":{"rendered":"Regulation of Respiration"},"content":{"rendered":"<p><!--:en--><\/p>\n<h2 id=\"links\">Links<\/h2>\n<p><a href=\"http:\/\/www.nature.com\/principles\/ebooks\/introduction-to-cell-biology-4570805\/4569900\">Principles Module 26<\/a><\/p>\n<p><a href=\"http:\/\/www.nature.com\/principles\/ebooks\/introduction-to-cell-biology-4570805\/4569889\">Principles Module 27<\/a><\/p>\n<h2 id=\"objectives\">Objectives<\/h2>\n<ul>\n<li>Describe the general principles of the regulation of metabolic pathways<\/li>\n<li>Discuss how cells transform energy in the absence of oxygen<\/li>\n<li>Provide examples of how glycolysis and the Krebs cycle are the \u2018backbone\u2019 of metabolism<\/li>\n<\/ul>\n<h2 id=\"keypoints\">Key points<\/h2>\n<ul>\n<li>Metabolism is regulated through feedback loops\n<ul>\n<li>products of the interconnected pathways act as signals to reduce flux through the pathway<\/li>\n<li>examples include ATP, citrate, NADH<\/li>\n<\/ul>\n<\/li>\n<li>Metabolic pathways tend to be regulated at reactions that are highly spontaneous (large negative \u0394G)\n<ul>\n<li>Phosphofructokinase catalyzes the rate-limiting step in glycolysis, and is inhibited by a high concentration of ATP (\u0394G = \u201325.9 kJ\/mol)<\/li>\n<li>several enzymes of the Krebs Cycle are inhibited by NADH and\/or their product<\/li>\n<\/ul>\n<\/li>\n<li>Cells can continue to transform high-energy compounds in the absence of oxygen, but at much lower efficiency\n<ul>\n<li>key concept of anaerobic respiration is to provide a \u2018sink\u2019 for electrons<\/li>\n<li>there are a number of anaerobic respiration pathways\n<ul>\n<li>alcohol fermentation pathway\n<ul>\n<li>glycolysis produces pyruvate and yields a little ATP and NADH<\/li>\n<li>pyruvate is oxidized to acetaldehyde, which is reduced to ethanol by NADH, thus regenerating NAD+ needed for glycolysis<\/li>\n<\/ul>\n<\/li>\n<li>lactic acid fermentation pathway\n<ul>\n<li>glycolysis produces pyruvate and yields a little ATP and NADH<\/li>\n<li>pyruvate is directly reduced to lactate by NADH, thus regenerating NAD+<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>Glycolysis and the Krebs cycle form the backbone of cellular metabolism\n<ul>\n<li>the products of glycolysis (pyruvate, acetyl-CoA) are used by the cell in the production of sugars, fatty acids, and amino acids<\/li>\n<li>the products of the Krebs cycle are used in the production of amino acids and nucleotides<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2 id=\"in-classactivities\">In-class activities<\/h2>\n<ul>\n<li>Continue your metabolic map, adding in the general points of regulation discussed in class.<\/li>\n<\/ul>\n<h2 id=\"questionsforpractice\">Questions for Practice<\/h2>\n<ul>\n<li>Name three products of respiration that regulate flux through the pathway. How is this adaptive to the cell?<\/li>\n<li>Enzymes in respiration that are most subject to regulation tend to have a property in common. What is that property? Why are these steps key to regulation?<\/li>\n<li>Why is anaerobic respiration useful to the cell, even though it is much less efficient than aerobic respiration?<\/li>\n<li>List the four classes of biological macromolecules and indicate the metabolic source of each class of molecule.<\/li>\n<\/ul>\n<p><!--:--><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Links Principles Module 26 Principles Module 27 Objectives Describe the general principles of the regulation of metabolic pathways Discuss how cells transform energy in the absence of oxygen Provide examples of how glycolysis and the Krebs cycle are the \u2018backbone\u2019 of metabolism Key points Metabolism is regulated through feedback loops products of the interconnected pathways [&hellip;]<\/p>\n","protected":false},"author":40,"featured_media":0,"parent":447,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-130","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/pages\/130","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/users\/40"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/comments?post=130"}],"version-history":[{"count":1,"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/pages\/130\/revisions"}],"predecessor-version":[{"id":516,"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/pages\/130\/revisions\/516"}],"up":[{"embeddable":true,"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/pages\/447"}],"wp:attachment":[{"href":"https:\/\/sites.owu.edu\/wolverton\/wp-json\/wp\/v2\/media?parent=130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}