Pehea he whakangotangota? momo wehenga

tīmata katoa pūtau tona ora, ka wehea i te matua, ka mutu ake te, hoatu te whai wāhi ki te puta ki a ratou pūtau tamahine. whakaratohia Nature neke atu i te kotahi te ara o wehewehe i te matua, i runga i to ratou hanganga rānei.

Methods o wehewehenga pūtau

Wehewehe i te matua, tei runga i te momo pūtau :

- whakangotangota ā-rua (kitea i roto i ngā prokaryotes).

- amitosis (hāngai ara wehenga).

- whāū (noa i roto i eukaryotes).

- pūira (mō te wehewehe pūtau iroriki).

E takoto momo wehenga i te āhua me te hāngai ki te hanganga o te pūtau, me te mahi mahi te reira i roto i te macroorganism i tahaki ranei.

whakangotangota-rua

Nuinga o ngā wā i kitea tenei momo i roto i ngā pūtau prokaryotic. Kei a ia i roto i te rearua te rāpoi ngota pītauira porohita. Kei te pera ka karanga whakangotangota pūtakerua o te karihi no o te pūtau whaea i reira e rua tamahine rite rahi.

I muri i te mea ira (DNA ranei RNA muingota) Kua kua rite i runga i, i.e. rererua reira, i haamata te taiepa pūtau ki te hanga i te arai hake, āta te nei maaro ka tuwhatuwhaia cytoplasm kia rua nga wahi āhua rite.

Ko te tukanga wehewehe tuarua i huaina hua pāhiwihiwi whakangotangota ā-rua ranei. I roto i tenei take, puta nga taiepa pūtau wahi protrusion, āta te nei tipu. I muri i te "whatukuhu" me te rahi o te pūtau whaea ka kia rite, e wehea ratou. He wahi o te taiepa pūtau synthesized te ano.

amitosis

Ko tēnei wehenga o te karihi rite ki te hunga whakaahuatia ana i runga, me te rerekētanga i reira he kahore tuaruatia ai o te rauemi ira. I whakaahuatia tuatahi tenei tikanga e Remak kaikoiora. puta tenei āhuatanga i roto i ngā pūtau pathologically puta (huringa mārere), a ka he te täkupu whaiaroaro mo ate kiko, ngohe me te taupoki io.

huaina te tukanga ko amitosis whakangotangota no te mau i te pūtau tona mahi, a ka kore e ngaro ratou rite i roto i whāū pūira. E whakamārama ana tēnei i te āhuatanga rerekē e pā ana ki te tukanga wehewehenga pūtau. I tua atu, haere matua wehenga tika kahore muka, na tohaina te pūpūira pūtau tamahine te mangai. I roto i te whai, e kore e taea e taua pūtau whakamahi i te huringa mitotic. I te tahi taime, ka rite ki te hua o te amitosis i hanga pūtau multinucleated.

whāū

Tenei whakangotangota autaki. Nuinga o ngā wā i kitea i roto i ngā pūtau eukaryotic. Ko te rerekētanga matua o tenei tukanga takoto i roto i te meka e tamaiti me ngā pūtau whaea i roto i te taua maha o ngā pūira. Na roto i tenei tautoko te tinana e te maha e hiahiatia o ngā pūtau, me te taea tukanga houtanga me te tupu. Ko te whāū pūira tuatahi i roto i te pūtau kararehe whakaahuatia Flemming.

wehea te tukanga o wehewehe i te karihi i roto i tenei take e tika i runga i interphase me te whāū pūira. Interphase - he āhua o te pūtau okioki i waenganui wehenga. Ka taea e wehewehe te reira e rave rahi ngā wāhanga:

1. wā presynthetic - tupu pūtau, piki reira pūmua me te warowaihā, te kaha synthesized ATP (adenosine triphosphate).

2. wā waihanga - rererua te rauemi ira te.

3. wā postsynthetic - e rererua te huānga pūtau, i reira he pūmua e hanga ake te muka e arai ana.

Ko te wāhanga o te whāū pūira

Ko te wehenga o te karihi o ngā pūtau eukaryotic - he tukanga i te mea e tika ana mo te hanganga o te atu organelles - centrosomes. Kei tata te karihi, me tona mahi matua, ko te ki te hanga i organelles hou - muka. āwhina ana tēnei hanganga ki tuwha te taurite te pūira i waenganui i ngā pūtau tamahine.

E ngā wāhanga e wha o te whāū pūira:

1. Prophase: pūpūira i roto i te karihi condenses i te chromatids, e te hunga e tata ana e haere i te centromeres i roto i takirua ki te hanga i ngā pūira. Nucleoli tareka ia, titaria ki nga amo o te centrioles pūtau. muka wehenga i hanga.

2. Metaphase: kua whakaritea nga pūira i roto i te rārangi haere i roto i te pokapū o te pūtau ki te hanga i te paraharaha metaphase.

3. Anaphase: chromatids te mahuetanga i te pokapū pūtau ki nga amo, me ka wehea ki e rua centromere. Ko te taea tenei kaupapa te mea o te muka wehenga, e heke, ka totoro pūira i roto i ngā tohutohu rerekē nga miro o nei.

4. Telophase: i hanga karihi tamahine. Chromatids tahuri ano ki pūpūira, i hanga te karihi te, a i roto i reira - te nucleoli. Mutu wehenga katoa o te cytoplasm me taiepa pūtau hanganga.

endomitosis

Ko te hua i roto i te rauemi ira, e kore nei e whakarato mo te wehenga o te karihi, ka karanga endomitosis. Kei te kitea te reira i roto i te pūtau o ngā tipu me ngā kararehe. I roto i tenei take kahore he whakangaromanga o te cytoplasm me te membrane karihi, engari riro pūpūira ki ngā pūira, a ka dispiralized.

taea ana tēnei tukanga ki te whiwhi karihi polyploid te wahi nui haere te ihirangi DNA te. Taua koroni hanga pūtau kitea i roto i te wheua wheua. I tua atu, i reira he take, ka rererua te rāpoi ngota pītauira te, a ka noho tonu te tokomaha o ngā pūira te taua. E mohiotia ana ratou rite polythene, a taea ana ratou e kitea i roto i ngā pūtau ngārara.

Te tikanga whāū

wehenga Mitotic o te nucleus - ko te ara ki te mau tonu i te huinga tamau o pūira. pūtau tamahine i te huinga taua o ira rite te matua me katoa o nga āhuatanga tūturu ki reira. hiahiatia whāū te hoki:

- te tipu me te whanaketanga o ngā kaiao multicellular (i te hononga o ngā pūtau iroriki);

- displacement o te paparanga pūtau raro i te tihi me te whakakapinga ngā pūtau toto (erythrocytes, leukocytes, platelets);

- pakaru hanga kiko (i roto i te tahi mau kararehe te aravihi no te houtanga ko he fie mo te ora, pērā i pātangaroa me mokomoko);

- whakaputa uri tōtahi o ngā tipu me etahi kararehe (hātaretare).

pūira

wehewehe pūtau iroriki tikanga karihi rerekē ahua i somatic. Ka rite ki te hua, i whiwhi ai ia pūtau e whai hawhe te mōhiohio iranga atu ratou matua. Ko te tika tenei i roto i te tikanga ki te mau tonu i te maha tonu o ngā pūira i roto i ia pūtau o te tinana.

puta whāiti pūira i roto i rua ngā wāhanga:

- Tuhinga atamira;

- atamira equational.

Tika i roto i te tukanga he taea anake i roto i ngā pūtau ki te ara maha o ngā pūira (diploid, tetraploid, me geksaproidnym t. D.). O te akoranga, tonu reira taea ki te haere pūira me ngā pūtau ki huinga rerekē o pūira, engari ka kore ai e taea te uri.

Tenei tikanga fakapapau'i sterility i roto i te mau faaipoiporaa interspecific. Mai i roto i te iroriki pūtau he huinga rerekē o pūira, fakafaingata'a'ia'i reira ratou fusion me te ahua o te uri taea, me te hua.

Ko te wehenga tuatahi o te whāiti pūira

tuaruatia wāhanga te ingoa o te hunga i roto i te whāū pūira: prophase, metaphase, anaphase, telophase. Ko reira e te tahi mau rerekētanga nui.

1. Prophase: huinga rua o pūira hanga te raupapa o panoni, haere i roto i rima ngā wāhanga (leptotena, zygotes, Paquita, diplotene, diakinesis). He ko tenei te whakawhetai katoa ki te conjugation me whakawhitinga-mo.

Conjugation - tenei tütakitanga o ngā pūira huirua. I roto i te leptotene therebetween hanga kakawaea kikokore, me te ka uru i roto i takirua pūira zygotene me te hua whiwhi i te hanganga o wha chromatids.

Crossover - te tukanga o ripeka-wāhanga o te utu i waenganui i tuahine chromatids ngā pūira huirua ranei. puta tenei i te wā pachytene. pekanga i hanga (chiasm) pūira. I roto i te tangata, ka taea e enei whakawhitinga i waenganui i te toru tekau-rima ki te ono tekau-ono. Ko te hua o tenei tukanga ko te heterogeneity iranga o te rauemi, rerekētanga ranei tohuhema hua.

A, no te reira mai te diplotene atamira o wha chromatids e ngaro complexes me pūira tuahine vzaimoottalkivayutsya. Diakinesis whakaoti te whakawhitinga i prophase ki metaphase.

2. Metaphase: raina pūira ake tata te weheruatanga o te pūtau.

3. Anaphase: pūira, arā, tonu o rua chromatids te mahuetanga ki te amo o te pūtau.

4. Telophase: wehewehe muka kua ngaro, hua i roto i te hanganga o ngā pūtau e rua ki te huinga haploid o pūira he rua te nui o DNA.

Ko te wehenga meiotic tuarua

Kei te karanga a hoki tenei tukanga "whāū, whāiti pūira." I roto i te kau i waenganui i nga wāhanga e rua e kore e DNA tāruarua puta, a ka tomo te rua o nga pūtau prophase o te huinga kotahi o pūira, i noho ia i muri i te 1 telophase.

1. Prophase: pūira whakawhāiti whitinga pokapū wehenga pūtau (ona toenga ki te rerekē amo o te pūtau), a ka hinga te takotoranga karihi i hanga muka wehenga tikanga hāngai ki te pou muka o te wehenga tuatahi.

2. Metaphase: kua kei pūira i te weheruatanga, i hanga te pereti metaphase.

E wehea pūira ki chromatids e anaana i roto i ngā tohutohu katoa: 3. Anaphase.

dispiralized i roto i ngā pūtau tamahine i hanga chromatids matua ki pūpūira: 4. Telophase.

I te mutunga o te wāhanga tuarua o te pūtau matua kotahi, i tatou āpiti wha ki te hawhe huinga o pūira. Ki te tango pūira wahi i roto i te taha ki te rārangi iroriki (e ko, te hanganga o ngā pūtau sex), ko te wehenga koi pāhiwihiwi, a kua hanga e e te pūtau kotahi ki te huinga haploid o pūira me toru whakaiti kuao, e kore e mau ana i te mōhiohio iranga e tika ana. E tika ana ki te whakarite i roto i te hua manu ratou me parāoa noho anake te hawhe o te rauemi ira o te pūtau matua. I tua atu, tenei puka o te wehenga karihi whakarato te ahua o ngā hou o ira, me te tupu parakore o ngā irarā.

I roto i te putanga māmā o te whāiti pūira vai ka reira he kotahi anake pae i roto i te wāhanga tuatahi, a i roto i te rua ki reira he crossover. Scientists whakaaro e tenei puka ko te kawainga whanaketanga o te whāiti pūira tikanga kaiao multicellular. Mahalo reira e te tahi atu huarahi o whakangotangota, e kore e ano e matau pūtaiao.