{"id":262968,"date":"2023-08-24T09:00:00","date_gmt":"2023-08-24T07:00:00","guid":{"rendered":"https:\/\/sherpas.com\/blog\/?p=262968"},"modified":"2023-09-12T16:01:03","modified_gmt":"2023-09-12T14:01:03","slug":"atmosphere-terrestre-vie","status":"publish","type":"post","link":"https:\/\/sherpas.com\/blog\/atmosphere-terrestre-vie\/","title":{"rendered":"L\u2019atmosph\u00e8re terrestre et la vie : d\u00e9couvre l&rsquo;incroyable lien \ud83c\udf0d"},"content":{"rendered":"\n<p>Tu auras peut-\u00eatre du mal \u00e0 y croire, mais <strong>l\u2019atmosph\u00e8re terrestre et la vie<\/strong> sont totalement li\u00e9es. On te dira m\u00eame que sans l\u2019atmosph\u00e8re, la vie sur cette plan\u00e8te ne serait tout simplement pas possible. Pour que tu puisses comprendre le fonctionnement, on te propose de remonter aux origines de cette plan\u00e8te. Allez, on y va ! \ud83d\ude80<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Atmosph\u00e8re, vie : origines \ud83c\udf0d<\/h2>\n\n\n\n<p>Si la vie a pu appara\u00eetre sur la plan\u00e8te, c&rsquo;est gr\u00e2ce \u00e0 la composition de <a href=\"https:\/\/fr.wikipedia.org\/wiki\/Atmosph%C3%A8re_terrestre\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/fr.wikipedia.org\/wiki\/Atmosph%C3%A8re_terrestre\" rel=\"noreferrer noopener nofollow\">l\u2019atmosph\u00e8re<\/a>. On t\u2019explique son \u00e9volution.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">L\u2019\u00e9volution de l\u2019atmosph\u00e8re \ud83d\udcc8&nbsp;<\/h3>\n\n\n\n<p>Comme toute chose, <strong>l\u2019atmosph\u00e8re a \u00e9volu\u00e9 avec le temps.<\/strong> Depuis la cr\u00e9ation de la Terre, celle-ci a chang\u00e9 au fur et \u00e0 mesure des ann\u00e9es pour devenir celle qu\u2019elle est actuellement.&nbsp;<\/p>\n\n\n\n<p>L\u2019atmosph\u00e8re primitive s\u2019est cr\u00e9\u00e9e en m\u00eame temps que la Terre il y a 4,6 milliards d\u2019ann\u00e9es. Elle \u00e9tait initialement compos\u00e9e de :&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>80% d\u2019eau (H2O) ;&nbsp;<\/li>\n\n\n\n<li>15% de dioxyde de carbone (CO2) ;<\/li>\n\n\n\n<li>5% de diazote (N2) ;<\/li>\n\n\n\n<li>0% de dioxyg\u00e8ne (O2) ;<\/li>\n<\/ul>\n\n\n\n<p>On explique cette composition de l\u2019atmosph\u00e8re au volcanisme tr\u00e8s intense qu\u2019il y avait alors. \ud83c\udf0b&nbsp;<\/p>\n\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>Pour info \ud83d\udca1<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p>Le volcanisme correspond \u00e0 l\u2019activit\u00e9 des volcans sur notre plan\u00e8te.<\/p>\n\n        <\/div>\n              <\/section>\n\n\n<section class=\"read-also\">\n    <p class=\"read-also__title\">\u00c0 lire aussi<\/p>\n            <div class=\"read-also__list\">\n            <p>D\u2019ailleurs, si tu veux en savoir plus sur les <a href=\"https:\/\/sherpas.com\/blog\/volcans\/\">volcans<\/a>, n\u2019h\u00e9site pas \u00e0 lire notre article sur le sujet !<\/p>\n\n        <\/div>\n    <\/section>\n\n\n\n<p>\u00c0 l\u2019inverse,<strong> aujourd\u2019hui, l\u2019activit\u00e9 volcanique sur Terre est tr\u00e8s faible<\/strong>. Tant mieux pour nous\u2026 Mais cela a donc men\u00e9 \u00e0 une \u00e9volution de l\u2019atmosph\u00e8re. Aujourd\u2019hui, elle se compose de :<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>79% de diazote (N2) ;<\/li>\n\n\n\n<li>21% de dioxyg\u00e8ne (O2) ;<\/li>\n\n\n\n<li>0,04% de dioxyde de carbone (CO2) ;<\/li>\n\n\n\n<li>et on note la pr\u00e9sence de traces d\u2019eau (H2O) ;<\/li>\n<\/ul>\n\n\n\n<p>\u2728 <strong>Ce qu\u2019il y faut retenir :<\/strong> On est pass\u00e9 d\u2019une atmosph\u00e8re principalement compos\u00e9e d\u2019eau et de dioxyde de carbone \u00e0 une atmosph\u00e8re compos\u00e9e de diazote et de dioxyg\u00e8ne.&nbsp;<\/p>\n\n\n<section class=\"relance\">\n        <div >\n                            <a href=\"https:\/\/sherpas.com\/cours\/svt\">\n                    <div class=\"relance__container\"\n                        >\n                        \n                                                        <picture>\n                            <source srcset=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/07\/relance-cours-particulier-6.jpg\" media=\"(min-width: 999px)\">\n                            <source srcset=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/07\/relance-cours-particulier-6.jpg\" media=\"(max-width: 999px)\">\n                                <img decoding=\"async\"\n                                    src=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/07\/relance-cours-particulier-6.jpg\"\n                                    alt=\"Personne qui donne des cours particuliers\"\n                                >\n                            <\/picture>\n                                                <div class=\"relance__content\">\n                            \n                                <div class=\"relance__title\"> <p>Si tu as encore un peu de mal avec les \u00e9l\u00e9ments qui composent notre atmosph\u00e8re, n&rsquo;h\u00e9site pas \u00e0 demander de l&rsquo;aide \u00e0 l&rsquo;un de nos Sherpas. Il sera ravi de t&rsquo;aider \u00e0 progresser en SVT !<\/p>\n<\/div>\n                                                        <button type=\"button\"\n                                    class=\"relance__button btn btn-white\">\n                                Par ici pour progresser en SVT ! \n                            <\/button>\n                        <\/div>\n                    <\/div>\n                <\/a>\n                    <\/div>\n    <\/section>\n\n    \n\n\n<h3 class=\"wp-block-heading\">L\u2019apparition de la vie gr\u00e2ce \u00e0 l\u2019eau liquide \ud83d\udca7<\/h3>\n\n\n\n<p>L\u2019\u00e9volution de la composition de l\u2019atmosph\u00e8re a engendr\u00e9 <strong>un changement d\u2019\u00e9tat de l\u2019eau.<\/strong> C\u2019est ce changement d\u2019\u00e9tat qui est responsable de l\u2019apparition de la vie sur terre.&nbsp;<\/p>\n\n\n\n<p>\ud83d\udc49 Lorsque la Terre s\u2019est form\u00e9e, elle \u00e9tait chaude bouillante. A ce moment-l\u00e0, l\u2019eau pr\u00e9sente \u00e9tait sous forme gazeuse. Avec le temps,<strong> la Terre s\u2019est peu \u00e0 peu refroidie et l\u2019eau est pass\u00e9e d\u2019un \u00e9tat gazeux \u00e0 un \u00e9tat liquide<\/strong>. On appelle ce passage la <strong>\u00ab&nbsp;liqu\u00e9faction<\/strong> \u00bb.&nbsp;<\/p>\n\n\n\n<p>L\u2019atmosph\u00e8re primitive \u00e9tait assez \u00e9paisse et la pression \u00e0 l\u2019\u00e9poque \u00e9tait tr\u00e8s \u00e9lev\u00e9e. Du coup, il ne pouvait pas y avoir d\u2019eau sous forme liquide, mais seulement sous forme de vapeur. Avec le temps, le sol s\u2019est refroidi et a entra\u00een\u00e9 le refroidissement de l\u2019atmosph\u00e8re. <strong>Ce changement de temp\u00e9rature a entrain\u00e9 un changement d\u2019\u00e9tat de l\u2019eau. Il y a eu un passage de l\u2019\u00e9tat gazeux \u00e0 l\u2019\u00e9tat liquide.<\/strong> \ud83d\udca7<\/p>\n\n\n\n<p>Ce passage \u00e0 l\u2019\u00e9tat liquide a fait que pendant plusieurs milliers d\u2019ann\u00e9es, il n\u2019a fait que pleuvoir sur Terre. C\u2019est comme \u00e7a que la temp\u00e9rature et la pression que l\u2019on conna\u00eet actuellement ont pu faire leur apparition.&nbsp;<\/p>\n\n\n\n<p>L\u2019eau liquide, en faisant son apparition, a permis de former les oc\u00e9ans. \ud83c\udf0a<\/p>\n\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>Pour rappel \ud83d\udca1<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p><!-- wp:paragraph --><\/p>\n<p>L\u2019eau existe sous trois formes :<\/p>\n<p><!-- \/wp:paragraph --> <!-- wp:list --><\/p>\n<ul>\n<li style=\"list-style-type: none\">\n<ul><!-- wp:list-item --><\/p>\n<li>liquide,<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --> <!-- wp:list-item --><\/p>\n<ul>\n<li style=\"list-style-type: none\">\n<ul>\n<li>gazeux,<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --> <!-- wp:list-item --><\/p>\n<ul>\n<li style=\"list-style-type: none\">\n<ul>\n<li>solide.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p><!-- \/wp:list-item --><\/p>\n<p><!-- \/wp:list --> <!-- wp:paragraph --><\/p>\n<p>\ud83d\udc49 L\u2019\u00e9tat de l\u2019eau d\u00e9pend de la pression et de la temp\u00e9rature qu\u2019il fait \u00e0 la surface de la terre.<\/p>\n<p><!-- \/wp:paragraph --><\/p>\n\n        <\/div>\n              <\/section>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"460\" height=\"259\" src=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/blog\/content\/uploads\/2023\/08\/eau-liquide-2.gif?func=bound&amp;w=460&amp;h=259\" alt=\"bulles d'eau \" class=\"wp-image-262974\" \/><\/figure><\/div>\n\n<section class=\"push \">\n        <div >\n            \n                                                <div class=\"push__container  qcd\" data-target=\"_self\" data-qcd=\"aHR0cHM6Ly9zaGVycGFzLmNvbS8=\" data-banner=\"2\" data-name=\"Cours part&amp;rsquo; global #1 = CPG1\" style=\"background-color: #F3FBF7\" >\n                                                                        <div class=\"push__teachers\">\n    <div class=\"d-flex justify-content-center d-md-none\">\n        <img decoding=\"async\" class=\"push__logo\" src=\"\/content\/themes\/sherpas-theme\/dist\/images\/logo.svg\" alt=\"Logo Sherpas\">\n    <\/div>\n    <div class=\"swiper\">\n        <div class=\"swiper-wrapper\">\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Jade2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Jade<\/p>                          <p class=\"push__teachers-school\">Sciences Po Paris<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">21\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Alma2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Alma<\/p>                          <p class=\"push__teachers-school\">ENS Paris-Saclay<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">24\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Olivier2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Olivier<\/p>                          <p class=\"push__teachers-school\">La Sorbonne<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">13\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Thibault2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Thibault<\/p>                          <p class=\"push__teachers-school\">ENS Paris Ulm<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">20\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/David2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">David<\/p>                          <p class=\"push__teachers-school\">EDHEC<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">25\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Simon2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Simon<\/p>                          <p class=\"push__teachers-school\">4e ann\u00e9e de m\u00e9decine<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">26\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Emilie2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Emilie<\/p>                          <p class=\"push__teachers-school\">Sciences Po Lyon<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">19\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Emma2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Emma<\/p>                          <p class=\"push__teachers-school\">Dauphine<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">15\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                    <\/div>\n    <\/div>\n<\/div>\n                                                    <div class=\"push__content\">\n                                                            <div  class=\"d-none d-md-block\" >\n                                    <img decoding=\"async\" class=\"push__logo\" src=\"\/content\/themes\/sherpas-theme\/dist\/images\/logo.svg\"\n                                        alt=\"Logo Sherpas\">\n                                <\/div>\n                                                                                        <div class=\"push__title\"><p>Ton premier cours particulier est offert ! <span role=\"img\" aria-label=\"\ud83c\udf81\">\ud83c\udf81<\/span><!-- notionvc: 91b6b7d7-50f2-46f4-ae1f-ecbabe834aad --><\/p>\n<\/div>\n                                                                                        <div class=\"push__text\"><p>Nos profs sont pass\u00e9s par les meilleures \u00e9coles et universit\u00e9s.<!-- notionvc: 21bb66b6-b36d-4ce8-8950-173722d75a1e --><\/p>\n<p>&nbsp;<\/p>\n<\/div>\n                                                        <div class=\"push__promo-button   \">\n                                                                                                    <div\n                                        class=\"btn btn-primary\"\n                                        style=\"color: #ffffff; border-color: ; background-color: \"\n\n                                    >\n                                        J&rsquo;EN PROFITE MAINTENANT !\n                                    <\/div>\n                                                            <\/div>\n                                                    <\/div>\n                                    <\/div>\n                                    <\/div>\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading\">L\u2019augmentation du dioxyg\u00e8ne dans notre atmosph\u00e8re \ud83d\udcc8<\/h2>\n\n\n\n<p>Juste au-dessus, on t\u2019a expliqu\u00e9 que le passage de l\u2019\u00e9tat gazeux \u00e0 l\u2019\u00e9tat liquide avait provoqu\u00e9 une pluie durant des milliers d\u2019ann\u00e9es. Eh bien, ces pluies ont justement permis la constitution des oc\u00e9ans\u2026 dans lesquels les premiers organismes vitaux ont vu le jour. \ud83d\ude31<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">L\u2019apparition du dioxyg\u00e8ne&nbsp;<\/h3>\n\n\n\n<p>Sur la plan\u00e8te, la vie est apparue il y a 3,5 milliards d\u2019ann\u00e9es (dans les oc\u00e9ans, donc) gr\u00e2ce \u00e0 des organismes que l\u2019on appelle des <strong>cyanobact\u00e9ries<\/strong>, capables de r\u00e9aliser la <a href=\"https:\/\/sherpas.com\/blog\/photosynthese\/\">photosynth\u00e8se<\/a>. \ud83c\udf31<\/p>\n\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>D\u00e9finition \u2728<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p>Les <strong>cyanobact\u00e9ries<\/strong> sont des bact\u00e9ries que l\u2019on appelle photosynth\u00e9tiques, puisqu\u2019elles r\u00e9alisent la photosynth\u00e8se. On peut aussi les appeler \u00ab\u00a0algues bleues \u00bb.<\/p>\n\n        <\/div>\n              <\/section>\n\n\n\n<p>\u00c0 partir de <strong>2,4 milliards d\u2019ann\u00e9es<\/strong>, des \u00e9changes gazeux ont eu lieu entre l\u2019atmosph\u00e8re et l\u2019oc\u00e9an permettant l\u2019enrichissement de l\u2019atmosph\u00e8re en dioxyg\u00e8ne.<\/p>\n\n\n\n<p>Comment on fait pour affirmer \u00e7a avec pr\u00e9cision ? Eh bien, on utilise des \u00e9l\u00e9ments naturels qui \u00e9taient pr\u00e9sents sur Terre bien avant nous. Comme les stromatolites et le fer ruban\u00e9. \ud83d\ude0a<\/p>\n\n\n\n<p>\ud83e\udea8 Les <strong>stromatolites<\/strong> sont une formation de calcaires qui r\u00e9sulte de l\u2019activit\u00e9 des cyanobact\u00e9ries. Les plus anciennes qui ont \u00e9t\u00e9 retrouv\u00e9es datent de -3,5 milliards d\u2019ann\u00e9es.<strong> Le CO2 qui est dissous dans l\u2019eau est utilis\u00e9 lors de la photosynth\u00e8se par les cyanobact\u00e9ries. <\/strong>L\u2019O2 est donc d\u00e9gag\u00e9.&nbsp;<\/p>\n\n\n<section class=\"read-also\">\n    <p class=\"read-also__title\">\u00c0 lire aussi<\/p>\n            <div class=\"read-also__list\">\n            <p>Si tu as besoin d\u2019un rappel sur le fonctionnement de la <a href=\"https:\/\/sherpas.com\/blog\/photosynthese\/\">photosynth\u00e8se,<\/a> n\u2019h\u00e9site pas \u00e0 lire notre article sur le sujet !<\/p>\n\n        <\/div>\n    <\/section>\n\n\n\n<p>\ud83e\udea8 Le<strong> Fer ruban\u00e9 <\/strong>se cr\u00e9e suite \u00e0 l\u2019accumulation de s\u00e9diments marins. Ils sont compos\u00e9s d\u2019oxydes de fer, ce qui fait qu\u2019ils ont cette couleur rouge. Ce sont eux qui indiquent la pr\u00e9sence d\u2019O2 dans l\u2019eau.<\/p>\n\n\n\n<p>Le fer pr\u00e9sent dans les oc\u00e9ans a \u00e9t\u00e9 oxyd\u00e9, cette oxydation a entra\u00een\u00e9 la cr\u00e9ation d\u2019ions Fe2+ et Fe3+. Ces ions ont produit de l\u2019oxyg\u00e8ne. Ainsi, ils ont permis l\u2019enrichissement de l\u2019O2 dans l\u2019atmosph\u00e8re \u00e0 partir de -2,4 milliards d\u2019ann\u00e9es. <strong>Ils ont ainsi permis l\u2019enrichissement de l\u2019O2 dans l\u2019atmosph\u00e8re \u00e0 partir de -2,4 milliards d\u2019ann\u00e9es<\/strong>.&nbsp;<\/p>\n\n\n\n<p>Il existe encore de nombreux indices qui permettent de corroborer tout \u00e7a. N\u00e9anmoins, le taux de dioxyg\u00e8ne pr\u00e9sent actuellement dans l\u2019atmosph\u00e8re est apparu il y a <strong>environ 500 millions d\u2019ann\u00e9es.<\/strong> Soit au m\u00eame moment que l\u2019explosion de la vie sur Terre. \ud83d\ude43<\/p>\n\n\n\n<p>\ud83d\udc49 Les cyanobact\u00e9ries, capables de r\u00e9aliser la photosynth\u00e8se, ont pu produire beaucoup de dioxyg\u00e8ne qui s\u2019est progressivement int\u00e9gr\u00e9 \u00e0 notre atmosph\u00e8re. C\u2019est gr\u00e2ce \u00e0 \u00e7a que les variations d\u2019O2 sont apparues.&nbsp;<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"600\" height=\"338\" src=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/blog\/content\/uploads\/2023\/08\/magie.gif?func=bound&amp;w=600&amp;h=338\" alt=\"Homme qui cr\u00e9e un arc-en-ciel avec ses mains en disant &quot;magique&quot;\" class=\"wp-image-262975\" \/><figcaption class=\"wp-element-caption\"><em>Alors non, l&rsquo;atmosph\u00e8re n&rsquo;est pas apparue comme par magie !<\/em><\/figcaption><\/figure><\/div>\n\n\n<h3 class=\"wp-block-heading\">Les variations du dioxyg\u00e8ne \ud83d\udcc8<\/h3>\n\n\n\n<p>Le dioxyg\u00e8ne varie en fonction de plusieurs \u00e9l\u00e9ments. <strong>Il varie en fonction des sources et des puits pr\u00e9sents sur Terre.<\/strong> Ceux-ci permettent de maintenir son niveau dans notre atmosph\u00e8re. \ud83d\ude42<\/p>\n\n\n\n<p>Pour que tu puisses te faire une id\u00e9e de qui sont les sources et qui sont les puits de dioxyg\u00e8ne, on te donne quelques exemples :<\/p>\n\n\n\n<p>\ud83d\udca7 Les sources<strong> produisent de l\u2019O2 et permettent un enrichissement de l\u2019atmosph\u00e8re en dioxyg\u00e8ne.<\/strong> Parmi les sources, on trouve notamment les \u00eatres vivants aquatiques ou terrestres qui r\u00e9alisent la photosynth\u00e8se. \ud83d\ude01<\/p>\n\n\n\n<p>\ud83d\udd73\ufe0f Les puits vont consommer le dioxyg\u00e8ne, et donc <strong>appauvrir l\u2019atmosph\u00e8re en O2. <\/strong>Parmi les puits, on trouve les \u00eatres vivants qui respirent, donc nous. Les combustions sont \u00e9galement des puits puisqu\u2019elles utilisent beaucoup d\u2019O2 pour fonctionner. \ud83d\ude25<\/p>\n\n\n\n<p>\ud83d\udc49 Les \u00e9changes de dioxyg\u00e8ne ont lieu entre <strong>la biosph\u00e8re et l\u2019atmosph\u00e8re<\/strong>.&nbsp;<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"939\" height=\"598\" src=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/blog\/content\/uploads\/2023\/08\/Schema-final-.png?func=bound&amp;w=939&amp;h=598\" alt=\"sch\u00e9ma des \u00e9changes dans l'atmosph\u00e8re \" class=\"wp-image-263065\" srcset=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=939 939w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=300 300w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=768 768w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=196 196w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=396 396w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=288 288w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=583 583w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=265 265w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=60 60w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=320 320w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=576 576w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=940 940w, https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2023\/08\/Schema-final-.png?w=1080 1080w\" sizes=\"(max-width: 939px) 100vw, 939px\" \/><figcaption class=\"wp-element-caption\"><em>Repr\u00e9sentation des \u00e9changes dans l&rsquo;atmosph\u00e8re <\/em><\/figcaption><\/figure><\/div>\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>Pour info \ud83d\udca1<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p>Les combustions li\u00e9es aux activit\u00e9s humaines viennent en suppl\u00e9ment des puits naturels qui existent d\u00e9j\u00e0.<strong> Elles vont engendrer une grande diminution de la teneur en dioxyg\u00e8ne.\u00a0<\/strong><\/p>\n\n        <\/div>\n              <\/section>\n\n\n\n<h3 class=\"wp-block-heading\">Le r\u00f4le de l\u2019ozone&nbsp;<\/h3>\n\n\n\n<p>La couche d\u2019ozone, on en parle pas mal ! Et c\u2019est enfin l\u2019heure pour toi de d\u00e9couvrir son r\u00f4le. <strong>Elle se forme dans l\u2019atmosph\u00e8re \u00e0 cause du rayonnement ultraviolet sur le dioxyg\u00e8ne. <\/strong>C\u2019est une couche protectrice et sans elle, l\u2019apparition et le d\u00e9veloppement de la vie n\u2019auraient pas \u00e9t\u00e9 possible dans les oc\u00e9ans ou sur Terre. \ud83c\udf0d<\/p>\n\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>Pour info \ud83d\udca1<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p>Tu seras peut-\u00eatre surpris, mais la couche d\u2019ozone ne se situe pas tr\u00e8s loin de nous ! Elle est entre <strong>20 et 50 km d\u2019altitude au-dessus du niveau de la mer.<\/strong> \ud83d\ude2f<\/p>\n\n        <\/div>\n              <\/section>\n\n\n\n<p>Vu qu\u2019on te parle d\u2019ultraviolet, c\u2019est l\u2019heure pour toi d\u2019aller jeter un \u0153il \u00e0 notre article sur les spectres. Si le sujet reste compliqu\u00e9 pour toi, n\u2019h\u00e9site pas \u00e0 faire appel \u00e0 l\u2019un de nos Sherpas pour qu\u2019il puisse t\u2019aider lors <a href=\"https:\/\/sherpas.com\/cours\/physique\">d\u2019un cours particulier<\/a> !&nbsp;<\/p>\n\n\n<section class=\"push \">\n        <div >\n            \n                                                <div class=\"push__container  qcd\" data-target=\"_self\" data-qcd=\"aHR0cHM6Ly9zaGVycGFzLmNvbS8=\" data-banner=\"2\" data-name=\"Cours part&amp;rsquo; global #2 = CPG2\" style=\"background-color: #F3FBF7\" >\n                                                                        <div class=\"push__teachers\">\n    <div class=\"d-flex justify-content-center d-md-none\">\n        <img decoding=\"async\" class=\"push__logo\" src=\"\/content\/themes\/sherpas-theme\/dist\/images\/logo.svg\" alt=\"Logo Sherpas\">\n    <\/div>\n    <div class=\"swiper\">\n        <div class=\"swiper-wrapper\">\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Cle\u0301mence2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Cl\u00e9mence<\/p>                          <p class=\"push__teachers-school\">HEC Paris<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">21\u20ac\/h\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Thibault2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Thibault<\/p>                          <p class=\"push__teachers-school\">ENS Paris Ulm<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">20\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Sophie2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Sophie<\/p>                          <p class=\"push__teachers-school\">Sciences Po Bordeaux<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">12\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Noemie2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">No\u00e9mie<\/p>                          <p class=\"push__teachers-school\">M2 en droit \u00e0 Assas<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">19\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Fanny2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Fanny<\/p>                          <p class=\"push__teachers-school\">Ponts ParisTech<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">19\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Simon2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Simon<\/p>                          <p class=\"push__teachers-school\">4e ann\u00e9e de m\u00e9decine<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">26\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Nicolas2x.png);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Nicolas<\/p>                          <p class=\"push__teachers-school\">CentraleSup\u00e9lec<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">17\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                                            <div class=\"swiper-slide\">\n                    <div class=\"push__teachers-card\">\n                        <div\n                            class=\"push__teachers-profil\"\n                            \n                            style=\"background-image: url(https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/content\/uploads\/2022\/01\/Victor2x.jpg);\"\n                        >\n                    <\/div>\n                         <p class=\"push__teachers-name\">Victor<\/p>                          <p class=\"push__teachers-school\">ESCP<\/p>                                                     <div class=\"push__teachers-note\">\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                                    <svg  class=\"active\" >\n                                        <use\n                                            xlink:href=\"\/content\/themes\/sherpas-theme\/dist\/images\/sprite.svg#star\"\/>\n                                    <\/svg>\n                                                            <\/div>\n                                                 <p class=\"push__teachers-price\">25\u20ac\/h<\/p>                     <\/div>\n                <\/div>\n                    <\/div>\n    <\/div>\n<\/div>\n                                                    <div class=\"push__content\">\n                                                            <div  class=\"d-none d-md-block\" >\n                                    <img decoding=\"async\" class=\"push__logo\" src=\"\/content\/themes\/sherpas-theme\/dist\/images\/logo.svg\"\n                                        alt=\"Logo Sherpas\">\n                                <\/div>\n                                                                                        <div class=\"push__title\"><p>Besoin d&rsquo;un prof particulier ? <span role=\"img\" aria-label=\"\u2728\">\u2728<\/span><!-- notionvc: 9b5ed38b-ea2e-4d3c-a3bb-f0091c2eedd2 --><\/p>\n<\/div>\n                                                                                        <div class=\"push__text\"><p>Nos profs sont l\u00e0 pour t&rsquo;aider \u00e0 progresser !<\/p>\n<p>&nbsp;<\/p>\n<p><!-- notionvc: 20490bdd-6579-484b-9d99-0ff0bc1aa8e7 --><\/p>\n<\/div>\n                                                        <div class=\"push__promo-button   \">\n                                                                                                    <div\n                                        class=\"btn btn-primary\"\n                                        style=\"color: ; border-color: ; background-color: \"\n\n                                    >\n                                        JE PRENDS UN COURS GRATUIT !\n                                    <\/div>\n                                                            <\/div>\n                                                    <\/div>\n                                    <\/div>\n                                    <\/div>\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading\">Le r\u00f4le du dioxyde de carbone \ud83d\udd04<\/h2>\n\n\n\n<p>Comme on te l\u2019a expliqu\u00e9 au d\u00e9but, l\u2019atmosph\u00e8re a perdu une grande quantit\u00e9 de dioxyde de carbone au fur et \u00e0 mesure des ann\u00e9es. Cette diminution est li\u00e9e aux diff\u00e9rents r\u00e9servoirs de carbone qui sont pr\u00e9sents sur la plan\u00e8te. On appelle ce ph\u00e9nom\u00e8ne <strong>le cycle du carbone.<\/strong>&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Le cycle de carbone&nbsp;<\/h3>\n\n\n\n<p>Les grands r\u00e9servoirs de carbone sont la <strong>biosph\u00e8re, la lithosph\u00e8re, l\u2019hydrosph\u00e8re et l\u2019atmosph\u00e8re<\/strong>. Les \u00e9changes entre eux mat\u00e9rialisent le cycle du carbone. Tous ces flux permettent de maintenir un \u00e9quilibre de carbone sur Terre. \ud83c\udf0d<\/p>\n\n\n\n<p>\ud83d\udc49 Les \u00e9changes de carbone sont quantifi\u00e9s sous forme de flux. L\u2019unit\u00e9 de mesure est <strong>la gigatonne que l\u2019on \u00e9crit (Gt\/an).<\/strong> Une gigatonne est \u00e9gale \u00e0 <strong>10 puissance 9 tonnes<\/strong>.&nbsp;<\/p>\n\n\n\n<p>\ud83d\udc49 Le plus grand r\u00e9servoir de carbone est la <strong>lithosph\u00e8re<\/strong>. Les roches carbonat\u00e9es (calcaire) ainsi que les roches carbon\u00e9es qui la composent (p\u00e9trole, gaz\u2026) permettent cela.&nbsp;<\/p>\n\n\n\n<p>\ud83d\udc49 Le flux naturel le plus important est celui qui existe gr\u00e2ce au m\u00e9canisme de la <strong>respiration et de la photosynth\u00e8se<\/strong>.&nbsp;<\/p>\n\n\n<section class=\"you-know\">\n                <div class=\"you-know__title\"><p>Rappel \u2728<\/p>\n<\/div>\n                        <div class=\"you-know__text\">\n            <p>L\u2019O2 et le CO2 sont essentiels pour la vie sur notre plan\u00e8te. En effet, le dioxyg\u00e8ne permet aux humains de vivre puisque c\u2019est notre principale source d\u2019\u00e9nergie. En consommant du dioxyg\u00e8ne, on rejette le dioxyde de carbone. Ce dioxyde de carbone est n\u00e9cessaire aux v\u00e9g\u00e9taux. Ils peuvent ainsi utiliser le CO2 pour produire de l\u2019O2. Souviens-toi, c\u2019est la photosynth\u00e8se ! En revanche, le dioxyde de carbone pr\u00e9sent en trop grande quantit\u00e9 sur la plan\u00e8te ce n\u2019est pas bon. Il impacte notre atmosph\u00e8re et entra\u00eene le r\u00e9chauffement climatique.<\/p>\n\n        <\/div>\n              <\/section>\n\n\n\n<h3 class=\"wp-block-heading\">Les r\u00e9servoirs \u00e0 carbone \ud83d\udee2\ufe0f<\/h3>\n\n\n\n<p>Sur Terre, il existe un grand nombre de r\u00e9servoirs \u00e0 carbone que l\u2019homme exploite. On pense notamment<strong> au charbon ou encore au p\u00e9trole<\/strong>. Malheureusement, l\u2019exploitation de ces r\u00e9servoirs est mauvaise pour notre plan\u00e8te. \ud83d\ude25<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"480\" height=\"214\" src=\"https:\/\/adymrxvmro.cloudimg.io\/v7\/sherpas.com\/blog\/content\/uploads\/2023\/08\/petrole.gif?func=bound&amp;w=480&amp;h=214\" alt=\"personnes contentes \" class=\"wp-image-262977\" \/><\/figure><\/div>\n\n\n<p>En effet, lors de la combustion du charbon ou encore du p\u00e9trole, une lib\u00e9ration importante de dioxyde de carbone a lieu. <strong>Cette lib\u00e9ration de CO2 dans l\u2019atmosph\u00e8re entra\u00eene une perturbation dans le cycle naturel du carbone.<\/strong> De plus, trop de dioxyde de carbone lib\u00e9r\u00e9 contribue \u00e0 acc\u00e9l\u00e9rer le r\u00e9chauffement climatique&#8230;&nbsp;<\/p>\n\n\n\n<p>Cette fiche de cours sur <strong>l\u2019atmosph\u00e8re terrestre et la vie<\/strong> touche \u00e0 sa fin. Tu sais \u00e0 pr\u00e9sent comment la vie a pu se d\u00e9velopper sur la plan\u00e8te ! N\u2019h\u00e9site pas \u00e0 nous laisser un commentaire pour nous dire si cet article a pu t\u2019\u00eatre utile ! \ud83d\ude09<\/p>\n\n\n<div class=\"kk-star-ratings kksr-auto kksr-align-center kksr-valign-bottom\"\n    data-payload='{&quot;align&quot;:&quot;center&quot;,&quot;id&quot;:&quot;262968&quot;,&quot;slug&quot;:&quot;default&quot;,&quot;valign&quot;:&quot;bottom&quot;,&quot;ignore&quot;:&quot;&quot;,&quot;reference&quot;:&quot;auto&quot;,&quot;class&quot;:&quot;&quot;,&quot;count&quot;:&quot;3&quot;,&quot;legendonly&quot;:&quot;&quot;,&quot;readonly&quot;:&quot;&quot;,&quot;score&quot;:&quot;4.7&quot;,&quot;starsonly&quot;:&quot;&quot;,&quot;best&quot;:&quot;5&quot;,&quot;gap&quot;:&quot;5&quot;,&quot;greet&quot;:&quot;Tu as aim\u00e9 cet article ?&quot;,&quot;legend&quot;:&quot;4.7\\\/5 - (3 votes)&quot;,&quot;size&quot;:&quot;24&quot;,&quot;title&quot;:&quot;L\u2019atmosph\u00e8re terrestre et la vie : d\u00e9couvre l\\u0026#039;incroyable lien \ud83c\udf0d&quot;,&quot;width&quot;:&quot;133.8&quot;,&quot;_legend&quot;:&quot;{score}\\\/{best} - ({count} {votes})&quot;,&quot;font_factor&quot;:&quot;1.25&quot;}'>\n            \n<div class=\"kksr-stars\">\n    \n<div class=\"kksr-stars-inactive\">\n            <div class=\"kksr-star\" data-star=\"1\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"2\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"3\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"4\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"5\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n    <\/div>\n    \n<div class=\"kksr-stars-active\" style=\"width: 133.8px;\">\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n                \n\n<div class=\"kksr-legend\" style=\"font-size: 19.2px;\">\n            4.7\/5 - (3 votes)    <\/div>\n    <\/div>\n","protected":false},"excerpt":{"rendered":"<p>Tu auras peut-\u00eatre du mal \u00e0 y croire, mais l\u2019atmosph\u00e8re terrestre et la vie sont totalement li\u00e9es. On (&#8230;)<\/p>\n","protected":false},"author":327,"featured_media":262969,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"category":[803,811],"tag":[],"class_list":["post-262968","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-apprendre-matiere","category-svt-biologie-2"],"acf":[],"_links":{"self":[{"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/posts\/262968","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/users\/327"}],"replies":[{"embeddable":true,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/comments?post=262968"}],"version-history":[{"count":0,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/posts\/262968\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/media\/262969"}],"wp:attachment":[{"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/media?parent=262968"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/category?post=262968"},{"taxonomy":"tag","embeddable":true,"href":"https:\/\/sherpas.com\/blog\/wp-json\/wp\/v2\/tag?post=262968"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}