{"id":8960,"date":"2018-01-29T14:31:12","date_gmt":"2018-01-29T13:31:12","guid":{"rendered":"http:\/\/www.gymhorice.cz\/?p=8960"},"modified":"2018-02-19T14:42:00","modified_gmt":"2018-02-19T13:42:00","slug":"o-sobcich-a-promyslenych-strategiich","status":"publish","type":"post","link":"https:\/\/www.gymhorice.cz\/?p=8960","title":{"rendered":"O sobc\u00edch a promy\u0161len\u00fdch strategi\u00edch"},"content":{"rendered":"

Jan Zrzav\u00fd a kolektiv autor\u016f
\nJak se d\u011bl\u00e1 evoluce (str. 157- 177)<\/em><\/p>\n

Sobeck\u00e9 geny<\/strong>
\nN\u011bkter\u00e9 typy gen\u016f se chovaj\u00ed sp\u00ed\u0161e jako parazit\u00e9, ne\u017e aby slou\u017eily organismu. Nahl\u00ed\u017e\u00edme na n\u011b
\nproto jako na tzv. genetick\u00e9 parazity. Zp\u016fsob\u016f jak se dan\u00fd gen sna\u017e\u00ed prosazovat a mno\u017eit se ke
\nsv\u00e9mu prosp\u011bchu je v\u00edce.
\nJednou z vhodn\u00fdch strategi\u00ed je hostitele nikdy neopou\u0161t\u011bt. Dok\u00e1\u017ee-li gen parazitovat
\nv cytoplazm\u011b vaj\u00ed\u010dek, dok\u00e1\u017ee se p\u0159es n\u011b dostat do dal\u0161\u00ed generace. \u0158\u00edk\u00e1me, \u017ee se p\u0159en\u00e1\u0161\u00ed vertik\u00e1ln\u011b,
\nz matky na potomstvo. V tomto p\u0159\u00edpad\u011b se parazit sna\u017e\u00ed hostitelsk\u00fdm samic\u00edm co nejm\u00e9n\u011b \u0161kodit.
\nParaziti, kte\u0159\u00ed se vertik\u00e1ln\u011b p\u0159enesou, se tak ocitnou z poloviny v samic\u00edch a z poloviny
\nv samc\u00edch. Ti, kte\u0159\u00ed jsou v samic\u00edch, jsou \u201espokojeni\u201c, proto\u017ee se mohou vertik\u00e1ln\u011b p\u0159en\u00e1\u0161et d\u00e1l ve
\nvaj\u00ed\u010dk\u00e1ch. Ti, kte\u0159\u00ed se v\u0161ak ocitnou v samc\u00edch, se sna\u017e\u00ed dostat pry\u010d. V\u011bt\u0161inou se sv\u00e9ho hostitele
\nsna\u017e\u00ed co nejrychleji zab\u00edt. Nejlep\u0161\u00ed pro n\u011b ov\u0161em je p\u0159em\u011bnit samce v samici. To d\u011blaj\u00ed nap\u0159.
\ncytoplazmatick\u00e9 bakterie v suchozemsk\u00fdch kor\u00fd\u0161\u00edch.
\nGeny se p\u0159en\u00e1\u0161ej\u00ed nejen vertik\u00e1ln\u011b, ale i horizont\u00e1ln\u011b (later\u00e1ln\u011b). Np\u0159\u00edklad kdy\u017e se virus uvoln\u00ed z
\njednoho genomu a vleze do jin\u00e9ho, zavle\u010de zavle\u010de tam s sebou t\u00e9\u017e kus genomu p\u016fvodn\u00edho
\nhostitele. Nebo kdy\u017e gen v eukaryotick\u00e9 bu\u0148ce p\u0159eleze z chloroplastu do j\u00e1dra a chloroplast pozd\u011bji
\nzanikne. I bakteri\u00e1ln\u00ed plazmid (mal\u00e1 molekula DNA) m\u016f\u017ee p\u0159el\u00e9zt pomoc\u00ed procesu konjugace do
\njin\u00e9 bu\u0148ky. Geny se zkr\u00e1tka \u0161\u00ed\u0159\u00ed celou biosf\u00e9rou, zdaleka nez\u016fst\u00e1vaj\u00ed jen ve sv\u00fdch \u201emate\u0159sk\u00fdch\u201c
\norganismech.<\/p>\n

Zv\u00fdhodn\u011bn\u00e9 pohlav\u00ed<\/strong>
\nAby m\u011bly parazituj\u00edc\u00ed geny co nejlep\u0161\u00ed mo\u017enost se roz\u0161\u00ed\u0159it, je pro n\u011b v\u00fdhodn\u00e9 dostat se na lich\u00fd
\npohlavn\u00ed chromozom Y (plat\u00ed pro ty, kter\u00e9 se ne\u0161\u00ed\u0159\u00ed p\u0159es sami\u010d\u00ed pohlavn\u00ed bu\u0148ky). Tak se toti\u017e po
\nmnoho generac\u00ed p\u0159en\u00e1\u0161ej\u00ed pouze v samc\u00edch a maj\u00ed mnohem vy\u0161\u0161\u00ed \u0161anci v\u00fdrazn\u011b up\u0159ednostnit pr\u00e1v\u011b
\njedno pohlav\u00ed. Jejich s\u00edly se pak net\u0159\u00ed\u0161t\u00ed mezi ob\u011b pohlav\u00ed a samci pak maj\u00ed velkou v\u00fdhodu.
\nJednou ze zaj\u00edmavost\u00ed Y je, \u017ee chromozom se st\u00e1le zmen\u0161uje.D\u016fvodem je jeho nep\u00e1rovost a
\ntud\u00ed\u017e nemo\u017enost rekombinace. Kdy\u017e se n\u011bjak\u00fd gen z chromozomu ztrat\u00ed, nav\u017edy zmiz\u00ed. U n\u011bkter\u00fdch
\ndruh\u016f hlodavc\u016f ji\u017e chromozom Y zmizel docela, samci tedy ji\u017e nejsou XY, n\u00fdbr\u017e X0. Evoluce
\nsekvenc\u00ed na chromozomu Y je v\u016fbec nejrychlej\u0161\u00ed u lid\u00ed a najdeme tu nejmen\u0161\u00ed podobnost s
\nchromozomem \u0161impanze (pouh\u00fdch 70 % oproti ostatn\u00edm 99 %). Co je jedine\u010dn\u011b mu\u017esk\u00e9 je tedy i
\nnejv\u00edce lidsk\u00e9.<\/p>\n

O v\u00fdchov\u011b<\/strong>
\nM\u016f\u017eeme se pt\u00e1t, zda chov\u00e1n\u00ed a v\u00fdvoj \u010dlov\u011bka ovliv\u0148uje sp\u00ed\u0161e v\u00fdchova \u010di geny. Inu, odpov\u011b\u010f je:
\noboj\u00ed. Tyto dva vlivy nelze ani jednozna\u010dn\u011b rozd\u011blit. Na vzniku fenotypu jedince se velmi v\u00fdznam\u011b
\npod\u00edlej\u00ed nejen geny a v\u00fdchova, ale i to, co se nov\u011b vznikaj\u00edc\u00edmu \u010dlov\u011bku p\u0159ihod\u00ed v d\u011bloze a p\u0159i
\nkojen\u00ed, a co p\u0159irozen\u011b nem\u011bn\u00ed jeho genotyp, ale modifikuje zp\u016fsob jeho \u010dten\u00ed a realizace
\n(\u201eepigenotyp\u201c).<\/p>\n

J\u00e1 nebo ty<\/strong>
\nMezi organismy prob\u00edhaj\u00ed \u010dasto sexu\u00e1ln\u00ed konflikty. Jako n\u00e1zorn\u00fd p\u0159\u00edklad uvedeme hladinov\u00e9
\nplo\u0161tice brusla\u0159ky (Gerris gracillicornis). Samice uzav\u0159ou sv\u00e9 genit\u00e1lie zvl\u00e1\u0161tn\u00edm \u0161t\u00edtkem, a t\u00edmto
\nzp\u016fsobem si vyb\u00edraj\u00ed nejsiln\u011bj\u0161\u00edho samce. Samec, kter\u00fd se ji sna\u017e\u00ed p\u0159inutit ke kopulaci a hroz\u00ed mu,
\n\u017ee neusp\u011bje, za\u010dne vys\u00edlat nohama vibrace, \u010d\u00edm\u017e p\u0159il\u00e1k\u00e1 vodn\u00ed pred\u00e1tory, t\u0159eba znakoplavku. A
\njeliko\u017e je samice vespod, hroz\u00ed j\u00ed se\u017er\u00e1n\u00ed, pokud nesvol\u00ed ke spojen\u00ed.
\nDal\u0161\u00ed zaj\u00edmavost\u00ed jsou hermafrodit\u00e9. Ti b\u011bhem kopulace soupe\u0159\u00ed o to, kdo bude otec a kdo
\nmatka. B\u00fdt matkou je toti\u017e velice energeticky n\u00e1ro\u010dn\u00e9 a tud\u00ed\u017e nev\u00fdhodn\u00e9. Samec jen zanech\u00e1
\nspermie a jde. Takov\u00e9to v\u00e1lky prob\u00edhaj\u00ed b\u011b\u017en\u011b i u rostlin mezi ty\u010dinkami a pest\u00edky.
\nSv\u011bt gen\u016f jist\u011b skr\u00fdv\u00e1 je\u0161t\u011b mnoh\u00e1 tajemstv\u00ed a d\u011bj\u00ed se v n\u011bm v\u011bci, o kter\u00fdch v\u011bdci doned\u00e1vna
\nnem\u011bli tu\u0161en\u00ed. Jist\u011b je\u0161t\u011b budeme \u017easnout, co v\u0161echno je mo\u017en\u00e9.<\/p>\n

 <\/p>\n

Blanka, 4.A<\/p>\n","protected":false},"excerpt":{"rendered":"

Jan Zrzav\u00fd a kolektiv autor\u016f Jak se d\u011bl\u00e1 evoluce (str. 157- 177) Sobeck\u00e9 geny N\u011bkter\u00e9 typy gen\u016f se chovaj\u00ed sp\u00ed\u0161e jako parazit\u00e9, ne\u017e aby slou\u017eily organismu. Nahl\u00ed\u017e\u00edme na n\u011b proto jako na tzv. genetick\u00e9 parazity. Zp\u016fsob\u016f jak se dan\u00fd gen sna\u017e\u00ed prosazovat a mno\u017eit se ke sv\u00e9mu prosp\u011bchu je v\u00edce. Jednou z vhodn\u00fdch strategi\u00ed je … p\u0159e\u010d\u00edst v\u0161e<\/a><\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[44],"tags":[45],"class_list":["post-8960","post","type-post","status-publish","format-standard","hentry","category-ze-supliku","tag-ze-supliku"],"_links":{"self":[{"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/posts\/8960","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=8960"}],"version-history":[{"count":2,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/posts\/8960\/revisions"}],"predecessor-version":[{"id":8963,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=\/wp\/v2\/posts\/8960\/revisions\/8963"}],"wp:attachment":[{"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8960"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8960"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gymhorice.cz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8960"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}