{"id":16,"date":"2018-06-30T14:54:01","date_gmt":"2018-06-30T14:54:01","guid":{"rendered":"http:\/\/schmidt-klein.dk\/?p=16"},"modified":"2018-07-01T10:45:24","modified_gmt":"2018-07-01T08:45:24","slug":"genetisk-variation","status":"publish","type":"post","link":"http:\/\/schmidt-klein.dk\/?p=16","title":{"rendered":"Genetisk variation"},"content":{"rendered":"

Uden genetisk variation, kan visse af evolutionsmekanismerne ikke fungerer. Det ligger jo i vores definition af evolution “Evolution sker n\u00e5r der er en \u00e6ndring i genhyppigheden inden for en population”. Hvis der kun er en variant af et gen, s\u00e5 kan hyppigheden af det ikke \u00e6ndres. Antallet kan naturligvis, men ikke fordelingen.<\/p>\n

Der er f\u00f8lgende tre prim\u00e6re kilder til genetisk variation i en population.<\/p>\n

    \n
  1. Mutationer. Alts\u00e5 pludselig \u00e6ndringer i arveanl\u00e6ggene (DNA). Der findes forskellige typer af mutationer, nogle har en stor effekt, andre lille eller ingen. Grundl\u00e6ggende er evolution\u00e6re \u00e6ndringer baseret p\u00e5 ophobning af mange mutationer. S\u00e5danne mutationer er f\u00f8rt videre, fordi de har givet individet der b\u00e6re dem egenskaber. Egenskaber der har gjort individerne bedre tilpasset.<\/li>\n
  2. Gen flow. Dvs. flytning af gener fra en population til en anden. Det er det samme som det vi kalder migration.<\/li>\n
  3. Sex. K\u00f8nnet formering kan introducerer nye genkombinationer i en population. Uk\u00f8nnet formering er ganske vist effektivt, men introducerer ikke nye genkombinationer.<\/li>\n<\/ol>\n

    Oversat og omarbejdet fra http:\/\/evolution.berkeley.edu<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    Uden genetisk variation, kan visse af evolutionsmekanismerne ikke fungerer. Det ligger jo i vores definition af evolution “Evolution sker n\u00e5r der er en \u00e6ndring i genhyppigheden inden for en population”. Hvis der kun er en variant af et gen, s\u00e5 kan hyppigheden af det ikke \u00e6ndres. Antallet kan naturligvis, men ikke fordelingen. Der er f\u00f8lgende […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[10,11,23],"class_list":["post-16","post","type-post","status-publish","format-standard","hentry","category-evolution","tag-biologi","tag-evolution","tag-genetik"],"_links":{"self":[{"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/posts\/16","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=16"}],"version-history":[{"count":1,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/posts\/16\/revisions"}],"predecessor-version":[{"id":17,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=\/wp\/v2\/posts\/16\/revisions\/17"}],"wp:attachment":[{"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/schmidt-klein.dk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}