Isakhiwo isikhungo cell. izici isakhi isikhungo cell

It is wafakazela ukuthi amaseli eziphilayo eukaryotic ethulwa uhlelo ulwelwesi, organelles ukwakha amaprotheni kanye nokusungulwa phospholipid. Nokho, lo mthetho kukhona okuhlukile ezibalulekile. Amabili organelle (cell isikhungo kanye ribosome), kanye organelles motion (cilia futhi flagella) non-ulwelwesi isakhiwo. Yini akha? Kuleli phephandaba sizozama ukuthola impendulo yalo mbuzo, kanye ukufunda isakhiwo amaseli isikhungo cell, ovame ukubizwa ngokuthi centrosome.

ukuthi amaseli ukuqukatha wonke isikhungo cell

Iqiniso lokuqala ososayensi nesithakazelo - ungubukhona ozikhethela lokhu organelle. Ngakho, ama-fungus ephansi - Chytridiomycota - futhi izitshalo ephakeme akusiyo. Njengoba kuvela, ulwelwe, kumaseli wesintu nokugcwaliseka izilwane kakhulu khona isikhungo cell kuyadingeka ukuze nemiphumela izinqubo mitosis futhi meiosis. Indlela ngowokuqala ukwabelana amaseli ukuphathwa kwabathintwayo, kanye nezinye - ocansini. umhlanganyeli ephoqelekile kokubili izinqubo ekuthandeni centrosome. Kwehlukana centrioles yayo izinti iseli kuhlukane kanye therebetween tensioning othini lokuphotha kanye siphinde sihlinzekele sesigcilikisha chromosome enamathiselwe lezi lokuluhlaza nezigxobo yeseli umama.

izifundo ezincane lwembula izici isikhungo cell isakhiwo. Ubunjwe komunye nemigwamanda eziningana aminyene - centrioles kuyiphi washintsha microtubules fanwise. Sizokwenza ukufunda kabanzi ukubukeka nokwakheka isikhungo cell.

Centrosome kumaseli interphase

Ngo ngibone umjikelezo wokuphila kwe amaseli isikhungo cell kungabonakala nenkathi ebizwa ngokuthi ukuba interphase. Eduze ulwelwesi nucleus ngokuvamile bahlela ezimbili microcylinder. Ngamunye wabo siqukethe amaprotheni tubules eqoqwe izingcezu ezintathu (ezintathu). Nine zalezi zakhiwo akha centrioles ebusweni. Uma bobabili (okuyinto kwenzeka kaningi), ukuthi akuphi ku nomunye engeli kwesokudla. Phakathi nenkathi yalokho ukuphila phakathi izigaba ezimbili isakhiwo iseli maphakathi esitokisini cishe okufanayo kuzo zonke eukaryotes.

I ultrastructure we centrosome

Ngempela ukukufunda ngokuningiliziwe isakhiwo isikhungo cell Lwenziwe ngokusebenzisa ngesibonakhulu electron. Ososayensi bathole ukuthi amasilinda centrosome babe izinhlangothi ezilandelayo: ubude bayo - 0.3-0.5 microns, ububanzi - 0.2 microns. Inombolo centrioles ngempela kabili ngaphambi division. Lokhu kuyadingeka ukuqinisekisa ukuthi kakhulu umama nendodakazi amaseli etholwe sokuhlukanisa isikhungo cell, ehlanganisa centrioles ezimbili. Izici isikhungo cell isakhiwo itholakala lokuthi ukuthi centrioles ukuthi bakha-ke, akuzona ezifanayo, omunye wabo - abavuthiwe (umama) - iqukethe izinto ezengeziwe: satellite peritsentriolyarny futhi ezihlobene yayo. centriole beya has a indawo ethize ebizwa cartwheel.

Ukuziphatha centrosomes ngesikhathi mitosis

Kuyaziwa ukuthi ukukhula umzimba, kanye ukukhiqizwa kabusha yayo kwenzeka ama-unit zokucathula ezingeni izilwane zasendle, okuyinto kuseli. Cell isakhiwo, indawo kanye umsebenzi iseli, kanye organelles yayo Cytology kubhekwe. Naphezu kweqiniso lokuthi abacwaningi baye baqhuba bacwaninga, isikhungo iseli ayikaqondwa kahle, nakuba yendima yayo ekuqhubeleni cell division cacisa ngokuphelele. Ngezinye prophase ka mitosis futhi meiosis e prophase ka meiosis centrioles washintsha ngase izinti iseli unina, futhi phambili kumiswa uthi lokuphotha intambo. Bona babiza centromeres wama-chromosomes constriction eyinhloko. Kuqakatheke ngani?

Anaphase lokuphotha cell

Ukuhlolwa of Boveri, uNeil A. nabanye ososayensi batholé ukuthi isakhiwo isikhungo cell kanye nokwenza imisebenzi yayo zihlobene kakhulu. Ukuba khona centrioles ezimbili, onokuphazamiseka kwengqondo okuguquguqukayo, ngokufanele maqondana izinti sezitokisi, bese imicu lokuphotha therebetween iqinisekisa i ngisho ukusatshalaliswa wama-chromosomes exhunywe kwi microtubules, ngamunye zezingongolo umzali cell.

Ngakho, inani chromosome kuyafana ngendodakazi amaseli ngokusebenzisa mitosis noma isigamu (e meiosis) kuka original umzali cell. ezithakazelisayo Ikakhulukazi Kuyaphawuleka ukuthi isakhiwo isikhungo cell kanye nezinguquko correlative roomates elihlobene ne izigaba cell umjikeleto wemphilo.

ukuhlaziywa kwamakhemikhali organelles

Ukuze uqonde kangcono umsebenzi nendzima cwaningo centrosome, yiziphi organic compounds afakiwe ngezithako zawo. Njengoba kungase kulindeleke, uholela amaprotheni. Engingakusho nje ukukhumbula ukuthi lokuphatselene nesakhiwo nemsebenti cell ulwelwesi nazo kuncike khona peptide molecule kuwo. Qaphela ukuthi kule amaprotheni centrosome ifa motility. Bayingxenye microtubules abizwa ngokuthi tubulins. Ukutadisha Sakhiwo sangaphandle futhi sangaphakathi isikhungo cell, sishilo izakhi asizayo: peritsentriolyarnye iziphuphutheki kanye ezihlobene centrioles. Bahlanganisa tseneksin futhi miritsitin.

Kukhona futhi amaprotheni elawula exchange of izinto organelle. Lokhu kinase futhi phosphatase - peptides ethize obhekene microtubule nucleation, okungukuthi, ukuze kwakhiwe esebenzayo-molecule-imbewu, oqala ngokuthi zamagama zokukhula osabalalayo futhi microfilaments.

Cell isikhungo ngokuba umhleli amaprotheni fibrous

Ngo Cytology ekugcineni bahlanganise ukuzwisisa we centrosome njengoba organelle main obhekene kumiswa microtubules. Ngenxa izifundo Ukuqoqela ndawonye K. Fultonamozhno baphikisa ngokuthi isikhungo cell inikeza le nqubo ngezindlela ezine. Ngokwesibonelo: sesigcilikisha polymerizing othini lokuphotha, ukwakha protsentrioley, ukudala uhlelo osabalalayo ka microtubules lamaseli interphase, futhi ekugcineni, synthesis yizakhi cilium eyinhloko. Le mfundo ekhethekile, okuyinto sici for the centrioles umzali. Ngokufunda isakhiwo kanye umsebenzi ulwelwesi cell, abacwaningi ukuthole ngesibonakhulu electron maphakathi iseli ngemva mitotic cell division, noma ekuqaleni mitosis. I-G2 esiteji of interphase kanye kusaqalwa prophase cilium iphele. Ngokusho ukwakheka kwamakhemikhali, liphethe molecule tubulin uwuphawu okungase kunqunywe ovuthiwe umzali centriole. Kusukela ekukhuleni kwamangqamuzana centrosomes kwenzeka? Cabanga bonke umehluko wemisindo nemiqondo yamagama le nqubo.

Izigaba kumiswa centrioles

Cytology sekuvela ukuthi le inkampani futhi umzali centrioles, ukwakha diplosomu azifani e isakhiwo. Ngakho, isakhiwo ovuthiwe insephe ungqimba peritsentriolyarnogo izidakamizwa - halo mitotic. Okugcwele nokuvuthwa indodakazi centrioles kuzokuthatha imizuzu engaphezu kuka isikhathi esisodwa emjikelezweni wokuphila amaseli. Ekupheleni esigabeni yeseli umjikelezo G1 centriole entsha yesibili kakade ukhonza njengomdala nomhleli microtubules nonekhono ukwakha izindikimba lokuphotha, futhi ekwakhekeni ezikhethekile organelle ukunyakaza. Kubo kungaba cilia futhi flagella okwenzeka lenyama unicellular (isib Euglena oluhlaza, ciliate-izicathulo), futhi abaningi ulwelwe Chlamydomonas isibonelo. Flagella microtubules esakhiwe ngokuhlanganisa isikhungo cell, ifakwe eziningi ulwelwe ezinhlamvu kanye germ cells bezilwane nabantu.

Indima centrosome kuseli umsebenzi

Sesibonile ukuthi omunye organelles kulencane yeselula (kuthatha ngaphansi kuka-1% amaseli) udlala indzima lesembili ukulawulwa umzimba kokubili nezitshalo nezilwane amaseli. Thuthuva ka lokuphotha kubandakanya ukwakheka indodakazi amaseli Izakhi zofuzo ezilimele. amathelevishini abo wama-chromosomes bengafani lemali evamile, okuholela chromosomal aberrations. Ngenxa yalokho - ukuthuthukiswa abantu angaphilile noma ukufa kwabo. Kwezokwelapha, luthole ukuthi ubuhlobo inani centrioles nengozi yokuba nesifo somdlavuza. Ngokwesibonelo, uma amaseli evamile isikhumba aqukethe centrioles ezimbili, izicubu biopsy ngesikhathi umdlavuza wesikhumba wembula nande zabo kuze kube 4.6. Le miphumela ubufakazi indima ebalulekile ye centrosome lilawulwa cell division. Kwakamuva idatha zokuhlola ukuphakamisa indima ebalulekile yalesi organelle ezinqutsheni ezokuthutha intracellular. Isakhiwo eziyingqayizivele isikhungo cell kuyivumela kushintshwe njengoba oluthile amaseli, futhi ushintsho yayo. Ngokuvamile ekuthuthukiseni amayunithi centrosome eseduze apharathasi Golgi, eduze nucleus futhi nabo kunikeza Integrative futhi okuwuphawu imisebenzi ukuqaliswa mitosis, meiosis, futhi ukufa kwamangqamuzana - apuptoza. Yingakho cytological yesimanje kubhekwe obalulekile owenza abantu babe nobunye centrosome organelle amaseli, unesibopho kokubili division yayo, futhi wonke umzimba jikelele.