{"id":3397,"date":"2020-02-25T20:59:32","date_gmt":"2020-02-25T19:59:32","guid":{"rendered":"http:\/\/evoluscience.fr\/?page_id=3397"},"modified":"2025-02-07T19:39:47","modified_gmt":"2025-02-07T18:39:47","slug":"activite-4","status":"publish","type":"page","link":"https:\/\/www.evoluscience.fr\/index.php\/cycle-4\/cinquieme\/5e-la-planete-terre-lenvironnement-et-laction-humaine\/chapitre-1-les-specificites-de-la-terre-au-coeur-du-systeme-solaire\/activite-4\/","title":{"rendered":"Activit\u00e9 2"},"content":{"rendered":"\n<div id=\"wp-block-themeisle-blocks-advanced-columns-d9c92ad1\" class=\"wp-block-themeisle-blocks-advanced-columns has-1-columns has-desktop-equal-layout has-tablet-equal-layout has-mobile-equal-layout has-vertical-unset\"><div class=\"wp-block-themeisle-blocks-advanced-columns-overlay\"><\/div><div class=\"innerblocks-wrap\">\n<div id=\"wp-block-themeisle-blocks-advanced-column-6a2bac43\" class=\"wp-block-themeisle-blocks-advanced-column\">\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\"><iframe loading=\"lazy\" src=\"https:\/\/anchor.fm\/laure-emilie-verkest\/embed\/episodes\/5-PT-Chp1Act4-ec255f\/a-a57pl6\" height=\"102px\" width=\"400px\" frameborder=\"0\" scrolling=\"no\"><\/iframe><\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-large-font-size wp-block-paragraph\">II. <strong>La formation de la vie dans le syst\u00e8me solaire<\/strong><\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-vivid-green-cyan-color has-text-color wp-block-paragraph\">Comment\nles sp\u00e9cificit\u00e9s de la Terre ont-elles permis la formation de la vie&nbsp;?<\/p>\n\n\n\n<div style=\"height:51px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f9e0c0\">Activit\u00e9 2&nbsp;: A partir d\u2019une vid\u00e9o, expliquer comment la vie a pu appara\u00eetre sur Terre en r\u00e9pondant aux questions puis comparer les temps \u00e9voqu\u00e9s.<\/p>\n\n\n\n<div style=\"height:52px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Comp\u00e9tences travaill\u00e9es&nbsp;:<\/em><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><em>R\u00e9aliser une \u00e9tude de documents.<\/em><\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li><em>Repr\u00e9senter le temps<\/em><\/li>\n<\/ul>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Rappel de la vid\u00e9o et des questions de la capsule:<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video controls src=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2025\/02\/Voyage-aux-origines-de-la-Terre-2-L-apparition-de-la-vie-sur-Terre.mp4\"><\/video><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Source : <a href=\"https:\/\/www.youtube.com\/watch?v=SFibjngYyEg\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.youtube.com\/watch?v=SFibjngYyEg<\/a><\/p>\n\n\n\n<div style=\"height:22px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Vers 3,9Ga (milliards d\u2019ann\u00e9es), une pluie de m\u00e9t\u00e9orites est tomb\u00e9e sur\nTerre. Ces m\u00e9t\u00e9orites contenaient des mol\u00e9cules d\u2019eau. Ce bombardement d\u2019une\ndur\u00e9e de 20Ma (millions d\u2019ann\u00e9es) a permis la formation des oc\u00e9ans.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">La pr\u00e9sence d\u2019eau (issue des m\u00e9t\u00e9orites) est une \u00e9tape essentielle de\nl\u2019apparition de la vie.<\/p>\n\n\n\n<div style=\"height:22px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ecrire la phrase pr\u00e9c\u00e9dente.<\/li>\n<\/ul>\n\n\n\n<div style=\"height:32px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Pour les questions suivantes,\nveillez \u00e0 faire des phrases reprenant la question pour comprendre les r\u00e9ponses\nplus tard.<\/em><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Quelles sont les deux raisons pour lesquelles la vie ne peut pas appara\u00eetre tout de suite&nbsp;?<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Que contiennent les m\u00e9t\u00e9orites de la seconde pluie&nbsp;?<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>La vie est apparue au niveau d\u2019une \u00ab&nbsp;soupe primitive&nbsp;\u00bb. Quels en sont les ingr\u00e9dients permettant l\u2019apparition de la vie&nbsp;?<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Quelles sont les plus anciennes formes de vie sur Terre&nbsp;(il y a environ 3,8Ga)?<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A partir de -3,5Ga, que produisent les stromatolithes permettant le d\u00e9veloppement de la couche d\u2019ozone et le d\u00e9veloppement de la vie&nbsp;?<\/li>\n<\/ul>\n\n\n\n<div style=\"height:28px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Les r\u00e9ponses sont dans la fiche de comp\u00e9tences.<\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">R\u00e9flexions et explications normalement en classe&nbsp;:<\/p>\n\n\n\n<div class=\"wp-block-media-text alignwide\" style=\"grid-template-columns:60% auto\"><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"325\" height=\"220\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/03\/stromatolithe-austra.gif\" alt=\"\" class=\"wp-image-4510 size-full\"\/><\/figure><div class=\"wp-block-media-text__content\">\n<p class=\"has-medium-font-size wp-block-paragraph\"> Les stromatolithes sont des structures form\u00e9es principalement de calcaire gr\u00e2ce \u00e0 l\u2019action de cyanobact\u00e9ries. Si ce sont nos premiers vrais fossiles datant de 3.5Ga, il en existe toujours notamment en Australie (milieu marin peu profond). <\/p>\n<\/div><\/div>\n\n\n\n<div style=\"height:46px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-media-text alignwide has-media-on-the-right\"><div class=\"wp-block-media-text__content\">\n<p class=\"has-medium-font-size wp-block-paragraph\"> Les stromatolites (du grec stroma, \u00ab tapis \u00bb et lithos, \u00ab pierre \u00bb) sont des structures en couches r\u00e9sultant de l\u2019activit\u00e9 de micro-organismes photosynth\u00e9tiques appel\u00e9s cyanobact\u00e9ries et d\u2019un pi\u00e9geage de particules s\u00e9dimentaires formant du calcaire.  <\/p>\n<\/div><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"335\" height=\"361\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/03\/stromato-fossile.jpg\" alt=\"\" class=\"wp-image-4515 size-full\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/stromato-fossile.jpg 335w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/stromato-fossile-278x300.jpg 278w\" sizes=\"auto, (max-width: 335px) 100vw, 335px\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div style=\"height:38px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.annabac.com\/sites\/annabac.com\/files\/depot\/images\/2014\/rootpbatSvtTleSproot\/ab8b47485fa5ca3a0974122363551150.png\" alt=\"\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Fonctionnement simplifi\u00e9 : Le stromatolithe grandit en alternant photosynth\u00e8se par les cyanobact\u00e9ries et production de calcaire le jour, et croissance horizontale des autres bact\u00e9ries la nuit.<\/p>\n\n\n\n<p class=\"has-text-align-right has-small-font-size wp-block-paragraph\">D&rsquo;apr\u00e8s  <a href=\"http:\/\/www.evolution-biologique.org\/histoire-de-la-vie\/monde-bacterien\/des-bacteries\/les-stromatolites.html\">http:\/\/www.evolution-biologique.org\/histoire-de-la-vie\/monde-bacterien\/des-bacteries\/les-stromatolites.html<\/a> <\/p>\n\n\n\n<p class=\"has-text-align-right has-small-font-size wp-block-paragraph\"><a href=\"https:\/\/www.annabac.com\/annales-bac\/developpement-des-stromatolites-et-evolution-de-l-atmosphere\">https:\/\/www.annabac.com\/annales-bac\/developpement-des-stromatolites-et-evolution-de-l-atmosphere<\/a><\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Nous trouvons des preuves de traces de vie pass\u00e9e sous forme de fossiles. <\/p>\n\n\n\n<div style=\"height:25px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Un&nbsp;<strong>fossile<\/strong>&nbsp;est une trace de vie qui a bien souvent \u00e9t\u00e9 pr\u00e9serv\u00e9e dans des roches s\u00e9dimentaires qui se sont form\u00e9es pendant des millions d&rsquo;ann\u00e9es.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video controls src=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2025\/02\/La-fossilisation.mp4\"><\/video><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Source : <a href=\"https:\/\/www.youtube.com\/watch?v=pJe5RmCg3Oo\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.youtube.com\/watch?v=pJe5RmCg3Oo<\/a><\/p>\n\n\n\n<div style=\"height:26px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Par exemple, un organisme meurt et tombe au fond de l\u2019oc\u00e9an. Des particules issues de l\u2019\u00e9rosion des roches (=s\u00e9diments) et transport\u00e9es par la rivi\u00e8re vont s\u2019accumuler sur lui. Le cumul des s\u00e9diments va entra\u00eener une compaction et une transformation en roche s\u00e9dimentaire.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Les restes solides des organismes pi\u00e9g\u00e9s dans les s\u00e9diments vont aussi subir une transformation&nbsp;: c\u2019est la fossilisation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Les fossiles trouv\u00e9s dans les roches s\u00e9dimentaires permettent de comprendre comment les \u00eatres vivants ont \u00e9volu\u00e9 au cours du temps.<\/p>\n\n\n\n<div style=\"height:38px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Voici ci-dessous une frise g\u00e9ologique montrant le d\u00e9coupage du temps g\u00e9ologique en grandes \u00e8res g\u00e9ologiques (frise du haut) puis le re-d\u00e9coupage en p\u00e9riodes g\u00e9ologiques (frise en bas):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34.png\" target=\"_blank\" rel=\"noreferrer noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"659\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-1024x659.png\" alt=\"\" class=\"wp-image-3412\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-1024x659.png 1024w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-300x193.png 300w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-768x494.png 768w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-520x335.png 520w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34-740x476.png 740w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/02\/image-34.png 1027w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><figcaption class=\"wp-element-caption\"> D\u2019apr\u00e8s <a href=\"http:\/\/banquemarcqsvt.blogspot.com\/2019\/01\/datation-de-la-croute-continentale-ts.html\">http:\/\/banquemarcqsvt.blogspot.com\/2019\/01\/datation-de-la-croute-continentale-ts.html<\/a> <\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">L&rsquo;unit\u00e9 Ma signifie millions d&rsquo;ann\u00e9es.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Il est aussi indiqu\u00e9 les organismes ayant v\u00e9cu \u00e0 ces \u00e9poques (informations d\u00e9termin\u00e9es gr\u00e2ce \u00e0 l&rsquo;\u00e9tude des fossiles).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">A retenir de la r\u00e9flexion normalement en classe : Les cyanobact\u00e9ries des stromatolithes ont permis l&rsquo;apparition du dioxyg\u00e8ne dans l&rsquo;atmosph\u00e8re. Il en existe toujours.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">+   Le temps g\u00e9ologique est d\u00e9coup\u00e9 en \u00e8res et p\u00e9riodes g\u00e9ologiques. Les noms des p\u00e9riodes g\u00e9ologiques seront utilis\u00e9s tout au long du cycle 4 (commencer \u00e0 les retenir).<\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"http:\/\/evoluscience.fr\/index.php\/cycle-4\/cinquieme\/5e-la-planete-terre-lenvironnement-et-laction-humaine\/chapitre-1-les-specificites-de-la-terre-au-coeur-du-systeme-solaire\/activite-4\/conclusion\/\" target=\"_blank\" rel=\"noreferrer noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"538\" height=\"538\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2019\/09\/conclusion.png\" alt=\"\" class=\"wp-image-370\" style=\"width:336px;height:336px\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/conclusion.png 538w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/conclusion-150x150.png 150w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/conclusion-300x300.png 300w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/conclusion-520x520.png 520w\" sizes=\"auto, (max-width: 538px) 100vw, 538px\" \/><\/a><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"http:\/\/evoluscience.fr\/index.php\/cycle-4\/cinquieme\/5e-la-planete-terre-lenvironnement-et-laction-humaine\/chapitre-1-les-specificites-de-la-terre-au-coeur-du-systeme-solaire\/activite-4\/devoir\/\" target=\"_blank\" rel=\"noreferrer noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"538\" height=\"538\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2019\/09\/devoirs.png\" alt=\"\" class=\"wp-image-428\" style=\"width:331px;height:331px\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/devoirs.png 538w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/devoirs-150x150.png 150w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/devoirs-300x300.png 300w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/devoirs-520x520.png 520w\" sizes=\"auto, (max-width: 538px) 100vw, 538px\" \/><\/a><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"http:\/\/evoluscience.fr\/index.php\/cycle-4\/cinquieme\/5e-la-planete-terre-lenvironnement-et-laction-humaine\/chapitre-1-les-specificites-de-la-terre-au-coeur-du-systeme-solaire\/activite-4\/bonus\/\" target=\"_blank\" rel=\"noreferrer noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"538\" height=\"538\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2019\/09\/bonus-1.png\" alt=\"\" class=\"wp-image-372\" style=\"width:291px;height:291px\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/bonus-1.png 538w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/bonus-1-150x150.png 150w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/bonus-1-300x300.png 300w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2019\/09\/bonus-1-520x520.png 520w\" sizes=\"auto, (max-width: 538px) 100vw, 538px\" \/><\/a><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"https:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/03\/5-PT-Chp1Act2-FC1.pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><img loading=\"lazy\" decoding=\"async\" width=\"735\" height=\"735\" src=\"http:\/\/evoluscience.fr\/wp-content\/uploads\/2020\/03\/pjiece_jointe-1.png\" alt=\"\" class=\"wp-image-4366\" style=\"width:335px;height:335px\" srcset=\"https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/pjiece_jointe-1.png 735w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/pjiece_jointe-1-300x300.png 300w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/pjiece_jointe-1-150x150.png 150w, https:\/\/www.evoluscience.fr\/wp-content\/uploads\/2020\/03\/pjiece_jointe-1-520x520.png 520w\" sizes=\"auto, (max-width: 735px) 100vw, 735px\" \/><\/a><\/figure>\n<\/div><\/div>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"parent":3335,"menu_order":5,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"class_list":["post-3397","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/pages\/3397","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/comments?post=3397"}],"version-history":[{"count":0,"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/pages\/3397\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/pages\/3335"}],"wp:attachment":[{"href":"https:\/\/www.evoluscience.fr\/index.php\/wp-json\/wp\/v2\/media?parent=3397"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}