{"id":871,"date":"2019-04-03T13:34:54","date_gmt":"2019-04-03T20:34:54","guid":{"rendered":"https:\/\/blogs.ubc.ca\/mrpletsch\/?p=871"},"modified":"2019-04-09T08:43:38","modified_gmt":"2019-04-09T15:43:38","slug":"the-respiratory-system-part-2-regulation-of-breathing-and-gas-exchange","status":"publish","type":"post","link":"https:\/\/blogs.ubc.ca\/mrpletsch\/2019\/04\/03\/the-respiratory-system-part-2-regulation-of-breathing-and-gas-exchange\/","title":{"rendered":"The Respiratory System Part 2: Regulation of Breathing and Gas Exchange"},"content":{"rendered":"<p><iframe loading=\"lazy\" width=\"700\" height=\"394\" src=\"https:\/\/www.youtube.com\/embed\/bHZsvBdUC2I?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<h3>3. Regulation of Breathing<\/h3>\n<p><b>Carbon Dioxide and Hydrogen Ions (H+) in the blood control breathing rate.<\/b><\/p>\n<ol>\n<li>CO2 will build up in the blood due to cellular respiration, increasing the concentration to a <b>threshold<\/b> level.<\/li>\n<li><b>Chemoreceptors in the aorta and carotid arteries detect this and signal the breathing centre in the medulla oblongata.<\/b><\/li>\n<li><b>The <\/b><b>medulla oblongata<\/b><b> begin signaling an inhalation response<\/b> &#8211; causing the diaphragm and intercostal muscles to contract. (increasing volume, and creating negative pressure &#8211; as learned earlier).<\/li>\n<li>Air flows into alveoli, and the alveolar walls expand and stretch<\/li>\n<li><b>Stretch Receptors<\/b><b> in the <\/b><b>alveoli walls<\/b><b> detect this stretching and signal the <\/b><b>medulla oblongata <\/b><b>to stop contraction of diaphragm\/intercostal muscles.<\/b><\/li>\n<\/ol>\n<h5>So breathing rate is controlled by the <b>autonomic nervous system<\/b> (unconscious functions such as heart rate, digestive processes, breathing).<\/h5>\n<h5 style=\"text-align: center;\">However, <b>breathing rate <\/b>is also subject to partial conscious control.<i>Why do you think that is?<\/i><\/h5>\n<p><b>Benefits:<\/b><\/p>\n<ul>\n<li>Hide from predators\/ quiet<\/li>\n<li>Speech<\/li>\n<li>Ability to dive\/enter water<\/li>\n<\/ul>\n<p><b>Mammalian Diving Reflex:<\/b><\/p>\n<ul>\n<li>Physiological reflexes that favor oxygen to heart\/brain<\/li>\n<li>Signals by holding breath, submersion in cold H20, and wetness in the nostrils<\/li>\n<li>Originates and signals from the same <b>chemoreceptors<\/b> in the carotid arteries.\n<ul>\n<li>Leads to:\n<ul>\n<li>1) <b>Bradycardia <\/b><\/li>\n<li>2) <b><b>Vasoconstriction <\/b><\/b>(especially in arms\/legs &#8211; leading to smaller circuit)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><iframe loading=\"lazy\" width=\"700\" height=\"394\" src=\"https:\/\/www.youtube.com\/embed\/UGhim3Gch2Q?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<h3>4. Gas Exchange<\/h3>\n<p><em>Please note: All equations related to gas exchange are not present in these notes. Instead, you will have to build the equations using these notes and looking at diagrams provided during our <strong>Gas Exchange: Building Equations <\/strong>group assignment. <\/em><\/p>\n<p>Recall:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-854\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-12.46.26-PM.png\" alt=\"\" width=\"777\" height=\"336\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-12.46.26-PM.png 777w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-12.46.26-PM-300x130.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-12.46.26-PM-768x332.png 768w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-12.46.26-PM-552x239.png 552w\" sizes=\"auto, (max-width: 777px) 100vw, 777px\" \/><\/p>\n<h5>External Respiration<\/h5>\n<p><b>Basics:<\/b><\/p>\n<ul>\n<li><i>There is diffusion of oxygen into the pulmonary capillaries and the diffusion of <\/i>CO2 (+ some H20) into the alveoli to be exhaled.<\/li>\n<li><i>Gas exchange occurs through <b>diffusion<\/b> alone &#8211; remember diffusion is movement from<b> high concentration to low concentration<\/b>:<\/i><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-872\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.21.49-PM.png\" alt=\"\" width=\"674\" height=\"111\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.21.49-PM.png 674w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.21.49-PM-300x49.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.21.49-PM-552x91.png 552w\" sizes=\"auto, (max-width: 674px) 100vw, 674px\" \/><\/p>\n<h5><b>Think: <\/b><i>How is diffusion of gas in the <\/i><b><i>alveoli<\/i><\/b><i> and <\/i><b><i>capillaries <\/i><\/b><i>possible?<\/i><\/h5>\n<figure id=\"attachment_873\" aria-describedby=\"caption-attachment-873\" style=\"width: 374px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-873\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.22.28-PM.png\" alt=\"\" width=\"374\" height=\"300\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.22.28-PM.png 374w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.22.28-PM-300x241.png 300w\" sizes=\"auto, (max-width: 374px) 100vw, 374px\" \/><figcaption id=\"caption-attachment-873\" class=\"wp-caption-text\">Figure 1: Alveolar gas exchange<\/figcaption><\/figure>\n<p><i>In Alveoli:<\/i><\/p>\n<ul>\n<li>Blood at alveoli <b>~37\u00b0C <\/b>and a pH of ~7.38.<\/li>\n<li>Conditions cause <b>oxygen<\/b> to bind with the <b>available <\/b><b>hemoglobin<\/b> in the blood.<\/li>\n<li>This creates <b>oxyhemoglobin<\/b> &#8211; HbO2<\/li>\n<li>As you learned, this improves blood\u2019s ability to carry oxygen by <b>70 times<\/b>.<\/li>\n<\/ul>\n<figure id=\"attachment_874\" aria-describedby=\"caption-attachment-874\" style=\"width: 288px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-874\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.23.20-PM.png\" alt=\"\" width=\"288\" height=\"328\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.23.20-PM.png 288w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.23.20-PM-263x300.png 263w\" sizes=\"auto, (max-width: 288px) 100vw, 288px\" \/><figcaption id=\"caption-attachment-874\" class=\"wp-caption-text\">Figure 2: Oxygen binding to hemoglobin to create oxyhemoglobin<\/figcaption><\/figure>\n<figure id=\"attachment_875\" aria-describedby=\"caption-attachment-875\" style=\"width: 333px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-875\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/ExaltedGroundedBumblebee-size_restricted.gif\" alt=\"\" width=\"333\" height=\"250\" \/><figcaption id=\"caption-attachment-875\" class=\"wp-caption-text\">Figure 3: Gas exchange at alveoli<\/figcaption><\/figure>\n<h5>Internal Respiration<\/h5>\n<p><i>In the tissues:<\/i><\/p>\n<ul>\n<li><b>Temperature in tissue capillaries is ~38\u00b0C and a pH of ~7.35 (warmer\/more acidic than alveoli)<\/b>\n<ul>\n<li>Conditions cause <b>hemoglobin<\/b> to release oxygen.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<ul>\n<li><b>Oxyhemoglobin (HbO2) returns to hemoglobin (Hb) and and Oxygen (O2)<\/b><\/li>\n<\/ul>\n<ul>\n<li>Fluids\/oxygen\/nutrients enter tissues (remember last unit?)<\/li>\n<\/ul>\n<figure id=\"attachment_800\" aria-describedby=\"caption-attachment-800\" style=\"width: 789px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-800\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/02\/Screen-Shot-2019-02-25-at-7.30.46-PM.png\" alt=\"\" width=\"789\" height=\"444\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/02\/Screen-Shot-2019-02-25-at-7.30.46-PM.png 789w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/02\/Screen-Shot-2019-02-25-at-7.30.46-PM-300x169.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/02\/Screen-Shot-2019-02-25-at-7.30.46-PM-768x432.png 768w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/02\/Screen-Shot-2019-02-25-at-7.30.46-PM-552x311.png 552w\" sizes=\"auto, (max-width: 789px) 100vw, 789px\" \/><figcaption id=\"caption-attachment-800\" class=\"wp-caption-text\">Figure 4: Capillary fluid exchange<\/figcaption><\/figure>\n<ul>\n<li>On the <b>venule <\/b>side of the tissue capillaries, a <b>higher osmotic pressure<\/b> pushes water\/CO2 and waste back into the capillaries.<\/li>\n<li>The <b>CO<\/b><b>2<\/b> reacts with <b>H20<\/b> to create <b>carbonic acid<\/b> (H2CO3 )<\/li>\n<\/ul>\n<figure id=\"attachment_876\" aria-describedby=\"caption-attachment-876\" style=\"width: 319px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-876\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.26.23-PM.png\" alt=\"\" width=\"319\" height=\"165\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.26.23-PM.png 319w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.26.23-PM-300x155.png 300w\" sizes=\"auto, (max-width: 319px) 100vw, 319px\" \/><figcaption id=\"caption-attachment-876\" class=\"wp-caption-text\">Figure 5: Carbon dioxide and water bind to make carbonic acid<\/figcaption><\/figure>\n<ul>\n<li><b>Carbonic acid<\/b> (H2CO3 ) -&gt; Quickly <b>dissociates<\/b> into <b>Bicarbonate ions<\/b><b> (<\/b><b>HCO<\/b><b>3<\/b><b>&#8211;<\/b> <b>) and hydrogen ions (<\/b><b>H<\/b><b>+<\/b><b> ), catalyzed by <span style=\"text-decoration: underline;\">carbonic anhydrate<\/span>.<br \/>\n<\/b><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-877\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.27.50-PM.png\" alt=\"\" width=\"775\" height=\"231\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.27.50-PM.png 775w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.27.50-PM-300x89.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.27.50-PM-768x229.png 768w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.27.50-PM-552x165.png 552w\" sizes=\"auto, (max-width: 775px) 100vw, 775px\" \/><\/p>\n<figure id=\"attachment_878\" aria-describedby=\"caption-attachment-878\" style=\"width: 608px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-878\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.28.25-PM.png\" alt=\"\" width=\"608\" height=\"479\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.28.25-PM.png 608w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.28.25-PM-300x236.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.28.25-PM-552x435.png 552w\" sizes=\"auto, (max-width: 608px) 100vw, 608px\" \/><figcaption id=\"caption-attachment-878\" class=\"wp-caption-text\">Figure 6: Fate of CO2 in blood<\/figcaption><\/figure>\n<h5><b>But, does all CO<\/b><b>2<\/b><b> bind with H20?<\/b><\/h5>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-879\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/giphy.gif\" alt=\"\" width=\"320\" height=\"180\" \/><\/p>\n<ul>\n<li>Some <b>CO<\/b><b>2<\/b> binds with <b>hemoglobin<\/b> to create <b>carbaminohemoglobin<\/b><b> (HbCO<\/b><b>2<\/b>)<\/li>\n<li>Some <b>CO<\/b><b>2 <\/b>dissolves in the blood plasma<\/li>\n<\/ul>\n<p><i>Return to alveoli:<\/i><\/p>\n<ul>\n<li><b>Blood returning the alveoli has:<\/b>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>Transporting bicarbonate (HCO3-) ions<\/li>\n<li>Transporting <i>some<\/i> dissolved <b>CO<\/b><b>2<\/b><\/li>\n<li>Hemoglobin is transporting <b>H<\/b><b>+<\/b><b> (Reduced hemoglobin &#8211; HHb)<\/b><\/li>\n<li><b><b>OR hemoglobin is transporting <\/b><\/b><b>CO<\/b><b>2<\/b> (carbaminohemoglobin &#8211;<b>HbCO<\/b><b>2<\/b>)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li><b>In the alveoli <\/b>temperature is lower and pH is higher (<b>~37\u00b0C \/ <\/b>pH of ~7.38)<\/li>\n<li>Hemoglobin releases <b>H<\/b><b>+<\/b> \u00a0and <b>CO<\/b><b>2<\/b><\/li>\n<li>Carbonic anhydrase (the enzyme that catalyzed the reaction before) catalyzes the reverse reaction from <b>bicarbonate<\/b> \u00a0and <b>hydrogen <\/b>to <b>carbonic acid<\/b>.<\/li>\n<li><b>Carbonic acid is catalyzed back into CO2 and H20.<\/b><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-880\" src=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.33.27-PM.png\" alt=\"\" width=\"766\" height=\"342\" srcset=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.33.27-PM.png 766w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.33.27-PM-300x134.png 300w, https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Screen-Shot-2019-04-03-at-1.33.27-PM-552x246.png 552w\" sizes=\"auto, (max-width: 766px) 100vw, 766px\" \/><\/p>\n<p><strong><u>Summary:<\/u><\/strong><\/p>\n<ul>\n<li>Oxygen moves into the alveolar capillaries due to diffusion \u2013 it binds with hemoglobin on RBCs for transport.<\/li>\n<li>Once at tissue capillaries, the change in conditions cause hemoglobin to release oxygen which crosses into the tissues.<\/li>\n<li>CO2 enters the capillaries at the venule side and can either: 1) Bind with H20 to produce carbonic acid, 2) Dissolve in the plasma, 3) Bind to hemoglobin to produce carbaminohemoglobin.<\/li>\n<li>The carbonic acid created quickly breaks down into bicarbonate ions and hydrogen ions.<\/li>\n<li>Back at the alveoli, the conditions change again, causing hemoglobin to release hydrogen ions and CO2. Carbonic anhydrase catalyzes the reverse reaction from bicarbonate and hydrogen into carbonic acid and then into CO2 and water.<\/li>\n<li>CO2 and water diffusion out into the alveoli and are exhaled.<\/li>\n<\/ul>\n<p>All information regarding <strong>tidal volume<\/strong> and <strong>vital capacity<\/strong> are in the background information provided in our lab <a href=\"https:\/\/blogs.ubc.ca\/mrpletsch\/files\/2019\/04\/Measuring-Lung-Capacity.docx\">Measuring Lung Capacity.<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p class=\"post-excerpt\">3. Regulation of Breathing Carbon Dioxide and Hydrogen Ions (H+) in the blood control breathing rate. CO2 will build up&#8230;<\/p>\n","protected":false},"author":48401,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1199859],"tags":[],"class_list":["post-871","post","type-post","status-publish","format-standard","hentry","category-biology-12"],"_links":{"self":[{"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/posts\/871","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/users\/48401"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/comments?post=871"}],"version-history":[{"count":4,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/posts\/871\/revisions"}],"predecessor-version":[{"id":886,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/posts\/871\/revisions\/886"}],"wp:attachment":[{"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/media?parent=871"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/categories?post=871"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.ubc.ca\/mrpletsch\/wp-json\/wp\/v2\/tags?post=871"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}