Matsayin rayuwa: menene muhimmancin bazuwar a cikin juyin halittar jinsi

Duk wani malami mai zurfi ko žasa ya san cewa juyin halitta shine samarda kwayoyin halittu masu yawa daga masu sauki da kuma bunkasa abubuwa masu rai a duniyar tun lokacin farkon rayuwa. Kuna tsammanin cewa tushen ci gaba da ƙwarewa a horarwa da kuma neman ci gaba (J.B. Lamarck) ko kuma a gwagwarmayar rayuwa da nasara na mai karfi (Charles Darwin), a cikin ikon yin taimako tare (PA Kropotkin) ko a cikin Masifu da yawa ba su da yawa (J. Cuvier) - ba ainihin mahimmanci ba ne. Abu mafi muhimmanci game da abin da muke tunani akai, menene muhimmancin bazuwar a cikin juyin halitta: jinsuna, jinsuna da bil'adama a matsayin duka? Menene daidaituwa ga kowannenmu? Kuma wata hatsari ko doka?

Ka'idar ka'idar

Kimiyyar zamani ta ba da shawara don la'akari da ka'idar juyin halitta a cikin ilimin haɗakarwa, ta yin amfani da ka'idojin ka'idar juyin halitta. Bugawa bisa ka'idar Darwiniyanci, wanda ya kara da ilimin kwayoyin kwayoyin halittu, embryology, kodododin halitta, jinsin halittu, da dai sauransu, an ba mu dukkanin ilimin da za a iya sanyawa a cikin 'yanci-bambanci-zaɓi ". A kowane matakai, menene muhimmancin samun dama a juyin halitta?

Biology na zamaninmu

A yau, mai sana'a mai fasaha ba zai shiga cikin jungle na kwayoyin halittu ba, kuma mai ilimin ilimin halitta ya bayyana mahimmanci game da ci gaba da jaririn mutum a hankali. Kuma kowane ilimin kimiyya mai zurfi zai kusanci amsar wannan tambayar game da irin rawar da ake ciki a cikin juyin halittar jinsuna daga hanyar hangen nesa. Bari muyi ƙoƙari mu fahimci ƙwararrun jarrabawa daga matsayi na musamman na ilimin kimiyya, wanda yawancin masana kimiyyar ba su tuna ba tun lokacin da ake makaranta.

Harshe: menene muhimmancin bazuwar a cikin juyin halittar jinsi

Kowane mutum yana tunawa: asalin halayen ya ƙayyade jigon halittar. Kwayoyin suna cikin sarkar DNA. DNA kunshi chromosomes, da chromosomes suna located a tsakiya. A duk wani kwayoyin da ke haifar da jima'i, jigilar chromosomes ne diploid (2n), wanda idan aka rarraba zuwa kashi ɗaya cikin rabin (n).

Inda ya sami damar? Amsar ita ce ko'ina. Game da canje-canje (canje-canje bazuwar) wanda zai iya canza daya ko kuma yawancin kadan kadan daga baya. Chromosomes suna musayar shafukan bazuwar (wucewa-kan), kuma lokacin da aka rabu da chromosomes a lokacin jigon halittu (gamete formation) wannan rikitarwa ba shi da ƙari. Da kyau, tare da haɗuwa da kwakwalwa tare da samuwar zygote, muhimmancin bazuwar abu ne mai mahimmanci.

Kuma idan a yau yau da tayi na embryoyo ya samu ta hanyar ci gaba da kwakwalwa da kuma aiki a farkon matakai na embryonic ontogenesis - to yaya zazzage ba zai iya rinjayar tasirin dangi ba?

Menene muhimmancin bazuwar a cikin juyin halittar jinsuna: bambancin

Abinda ke da muhimmanci na rayuwa, da ikon dukan abubuwa masu rai don samun sababbin halaye kuma, a sakamakon haka, inganta haɓakawa ga canza yanayin yanayi. Bambanci a cikin kwayoyin halitta shine tushen sauye-sauye, wanda yake da muhimmanci ga juyin halitta. Kuma babban abu a nan shi ne maye gurbin. Ba da wata sanarwa ba ko kuma a ƙarƙashin aikin mutagens, maimaitawa ko canza yawan adadin chromosomes a cikin kwayar halitta - dukkanin su ta ma'anar ba su da amfani ga wani mutum. A mafi kyau, suna tsaka tsaki. Amma tare da wasu canje-canje a cikin yanayi, wannan rashin daidaituwa ne kawai wanda zai zama babban mahimmanci a cikin ƙayyade halittu da suka fi dacewa.

Kuma idan an tabbatar da cewa ko da danniya iya zama wani mutagenic wakili, ba a ma maganar da duniya da gurbacewar muhalli kayayyakin rabin-rai na makamashin nukiliya?

Zabin yanayi shine mummunar haɗari a juyin halitta

Daga farawar zygote har zuwa farkon kwanakin balaga, zabin yanayi, kamar takobin Damocles, yana rataye akan dukan abubuwa masu rai. Zygote ba za ta taba zama jariri ba kawai saboda sun ci naman. Kuma wannan shi ne mafi muni wanda zai iya faruwa. Rashin haɗari yana cikin raguwa da tsafin dutsen mai fitattun wuta da kuma ragowar yawan mutane a cikin biyu, ko lalacewar kwakwa a cikin teku da kuma samun shi zuwa tsibirin tsibirin, inda zai iya haifar da sababbin mutane ko a'a.

Rashin gwagwarmayar zama a cikin yanayin da ya fi tsanani - intraspecific - ya tilasta wajan alade ta cinye 'yan uwanta cikin mahaifiyar uwarsa. A interspecies fafitikar yin makafi jħfa cuckoo qwai adoptive iyaye daga gida.

Duk da haka, menene amsar?

Amsar wannan tambaya, menene muhimmancin bazuwar a cikin juyin halittar jinsi, duk da hujja bayyanan, ba haka ba ne mai sauƙi. Tambayi masu ilimin tauhidi na ilmin lissafi - kuma a cikin ƙididdiga da logarithms zai tabbatar da cewa a cikin duniya babu wani abin da ya faru. Komai yana iya yiwuwa kuma mataki na yiwuwa yana da tabbas.

Iliminmu a fagen likitan lantarki da kuma nazarin sararin samaniya ya jagoranci bil'adama har zuwa bifurcation a cikin kimiyya. Ilimin da yawa zai iya buɗe sabon binciken zuwa wani gefe marar kuskure, kamar yadda, misali, pipin Krasin suna da raguwa na sararin samaniya, waɗanda ke da sha'awar ci gaban cosmonautics yayin da suke nema hanyoyin tafiya ta tsakiya.