Amitosis - ke iyindlela cell division

Ukujwayelaniswa ngolwazi oluqukethwe kulesi sihloko kuzokwenza umfundi ukuze ufunde kabanzi mayelana enye yezindlela of cell division - amitosis. Sizothola izici Yiqiniso yale nqubo, cabanga umehluko kusuka kwamanye izinhlobo division nokuningi.

Kuyini amitosis

Amitosis - uhlobo cell division ngqo. Le nqubo kungenxa evamile division of nucleus zibe izingxenye ezimbili. Nokho, bangase balahlekelwe isigaba ukwakha uthi lokuphotha ukwehlukana. A Ligation kwenzeka ngaphandle ukufingqa chromatin. Amitosis - inqubo esivela amaseli zezilwane nezitshalo, kanye lenyama.

Kusukela umlando nocwaningo

Robert Remak e 1841 wanikeza incazelo yenqubo amitosis okokuqala, kodwa igama ngokwayo kwenzeka kamuva kakhulu. Kakade 1882 isazi esidumile sezinto eziphilayo futhi imvelaphi histologist isiJalimane, Walter Flemming ahlinzekwa igama yesimanje yenqubo. Amitosis iseli imvelo ayeyivelakancane, kodwa ngokuvamile kungenzeka, ngoba kuyadingeka.

inqubo Izici

Njengoba cell division kwenzeka? Amitosis kuvame ukuvela nini kumaseli kokuba wanciphisa ukuhileleka mitotic. Ngakho, isethi amaseli wayezakufa ngenxa yokuguga noma ubunjalo izinguquko sokugembula, mukela kokufa kwakhe isikhathi esithile.

Amitosis - inchubo lapho isimo nucleus ngesikhathi interphase ukugcina izici zabo morphological: i nucleolus kungabonakala ngokucacile, kanye egobolondweni, DNA is hhayi ziphindaphindwe, chromatin - amaprotheni, iDNA RNA hhayi spiraleziruyutsya futhi ukuhlonza wama-chromosomes e-nucleus amaseli eukaryotic engekho.

Kukhona cell division ngokungaqondile - mitosis. Amitosis, ngokuphambene, ivumela cell ngemva division silondoloze umsebenzi wayo njengoba isici ukusebenza. Uthi lokuphotha (ngesakhiwo chromosome ukuhlukaniswa) lapho amitosis ayakhekanga, kodwa umongo namanje ahlukane phakathi, futhi yalokhu nqubo ukusatshalaliswa ongacabangi ukwaziswa kwezakhi zofuzo. Ukuntuleka kokukhulumisana inqubo cytokinetic okuholela ukukhiqizwa kwamaseli nge nuclei ezimbili, okuyinto angengene umjikelezo ejwayelekile ka mitosis esikhathini esizayo. Multiple ezinikezwa amitosis kungaholela ekwakhekeni amaseli nge sebuningini cores.

Isimo samanje

Amitosis njengendlela mqondo baqala ukuvela eziningi izincwadi kule minyaka engu-80 ngekhulu leminyaka lamashumi amabili. Kuze kube manje, kukhona ukusikisela ukuthi zonke izinqubo ukuthi yayikade okuvalelwe ngaphansi lo mqondo, eqinisweni nombono ongafanele ngesikhathi nicwaninga amaslayidi awukakulungeli. Ososayensi bakholelwa ukuthi lo mkhuba cell division, ephelezelwa ukubhujiswa esikhathini esidlule, kungaholela okufanayo ayeliqonda futhi bechaza amandla idatha. Nokho, ezinye izinqubo sesigaba kumaseli eukaryotic ayikwazi isibaluli mitosis noma meiosis. Isibonelo esimangalisayo lena isiqinisekiso kanye nenqubo macronuclear division (cell nucleus ciliates, usayizi esikhulu), ngesikhathi lapho abanye-chromosome ukuhlukaniswa izingxenye kuyinto naphezu kweqiniso lokuthi kwakhiwa uthi lokuphotha is ukwehlukana.

Kuyini ngenxa kwetintfo izinqubo cwaningo amitosis? Iqiniso lokuthi lesi simo kunzima ukunquma kuzici zalo morphological. ukuzimisela okunjalo kungathembeki. Ukungakwazi ukuze kuchazeke kahle izimpawu amitosis inqubo morphology esekelwe neqiniso lokuthi akuyona yonke okhalweni yenuzi kuwuphawu amitosis. Futhi ngisho Dumbbell ezakheke, okuyinto ngokucacile nucleus, ungakwazi kuphela ezihlobene uhlobo ugingqe. Futhi constriction nucleus kungenzeka ngenxa mkhuba omubi esandulele division by mitosis. Ngokuvamile-ke kwenzeka ngokushesha ngemva kokuba amitosis endomitosis (chromosome Ukubuyelela kabili indlela ngaphandle division sezitokisi, bese i-nucleus yayo). Ngokuvamile amitosis inqubo imiphumela kabili we kuyi-nucleus yengqamuzana. Ukuphindwa lesi simanga kudala sebuningini iseli nuclei. Ngakho amitosis kudala amaseli nge-chromosome setha uhlobo polyploid.

isiphetho

Kufinyeta, singasho ukuthi amitosis - inqubo lapho iseli sehlukaniswe uhlobo ngqo, okusho ubungako bokudlulisa yenzeka ezingxenyeni ezimbili. Inqubo ngokwaso akakwazi ukunikeza cell division ku alinganayo, neengcezu ezifanayo. Lokhu kusebenza futhi ulwazi zofuzo cell.

Le nqubo has eziningi umehluko abukhali kusukela division isigaba ngu mitosis. Umehluko omkhulu e lwe-mitosis futhi amitosis kungekho core igobolondo ekubhujisweni ngesikhathi amitosis nucleolus, futhi inqubo ukugeleza ngaphandle kumiswa uthi lokuphotha, nokunikeza ulwazi division. Cytokinesis ezimweni eziningi akuyona ihlukaniswe.

Okwamanje, azikho izifundo enkathini yesimanje, okungase asho ngokucacile ukuthi amitosis njengoba uhlobo cell ukonakala. Kuyefana nasendleleni le amitosis bezibona njengoba indlela cell division ngenxa yokubakhona encane kakhulu sokuhlukanisa lonke cell umzimba. Ngenxa amitosis mhlawumbe kangcono udluliselwe izinqubo zokulawula ezenzeka ngaphakathi amaseli.