El umjikelezo weseli Kuyinqubo eyisisekelo empilweni yamaseli, ebonakala ngochungechunge lwezehlakalo ezilandelanayo ezivumela ukuphindwaphindwa nokukhiqizwa kwamaseli amasha. Lezi zigaba, ezakha umjikelezo weseli, zilawulwa kakhulu futhi zilawulwa ukuze kuqinisekiswe ubuqotho nokusebenza okufanele kwenhlangano okukhulunywa ngayo. Kulesi sihloko, sizohlola ngokuningiliziwe ukuthi uyini umjikelezo weseli kanye nezigaba ezihlukahlukene eziwenza, sinikeze umbono wezobuchwepheshe nokungathathi hlangothi kule nqubo eyinkimbinkimbi yezinto eziphilayo.
Isingeniso kumjikelezo weseli
Umjikelezo umakhalekhukhwini kuyinqubo kubalulekile ukuze kuphile izinto eziphilayo. Iqukethe uchungechunge lwezehlakalo ezididiyelwe ezenzeka kusukela ekwakhekeni kweseli elisha ukuya ekuhlukaniseni kwalo libe amaseli amantombazane amabili. Phakathi nale nqubo, iseli libhekana nokukhula nokuphindaphinda kwezinto zalo zofuzo, ezaziwa ngokuthi i-DNA, kanye nokuhlukaniswa kwama-chromosome kanye nokuhlukaniswa okulinganayo kwama-organelles amaselula. Umjikelezo weseli uhlukaniswe izigaba eziningana, ngasinye sinomsebenzi othile futhi silawulwa ngokunembile ukuze kuqinisekiswe ubuqotho be-DNA kanye nokuzala kabusha kwamaseli okulungile.
Izigaba eziyinhloko yomjikelezo wamaseli Ziyi-interphase ne-mitosis. Ngesikhathi se-interphase, iseli lilungiselela ukuhlukana futhi lihlukanise, libe yizigaba ezintathu: isigaba se-G1, isigaba S, kanye nesigaba se-G2. Phakathi nesigaba se-G1, iseli liyakhula futhi ukuhlanganiswa kwamaprotheni nama-organelles adingekayo ekuhlukaniseni amaseli okulandelayo kwenzeka. Esigabeni sika-S, ingqamuzana liphindaphinda i-DNA yalo ukuze ingqamuzana ngalinye lendodakazi likwazi ukuthola ikhophi eliphelele. Isigaba se-G2 yisikhathi esengeziwe sokulungiselela ngaphambi kokungena ku-mitosis.
I-Mitosis yisigaba lapho iseli lihlukana libe amaseli amantombazane amabili afana neseli likamama. Lesi sigaba sihlukaniswe izigaba ezine: i-prophase, i-metaphase, i-anaphase ne-telophase. Ngesikhathi se-prophase, ama-chromosome ayancipha futhi i-mitotic spindle iqala ukwakheka. Ku-metaphase, ama-chromosome aqondana ku-metaphase plate. Khona-ke, ku-anaphase, ama-chromosome ahlukana futhi aqhubekele ezigxotsheni eziphambene zengqamuzana. Ekugcineni, ku-telophase, ama-chromosome afinyelela ezigxotsheni eziphambene futhi akhe ulwelwesi lwamangqamuzana olusha eduze kweqembu ngalinye lama-chromosome, ngaleyo ndlela akhiqize amangqamuzana amantombazane amabili.
Fases del ciclo celular
Umjikelezo wamaseli uyinqubo eqhubekayo futhi elawulwa kakhulu eyenzeka kuwo wonke amaseli e-eukaryotic. Ingahlukaniswa ngezigaba ezine eziyinhloko: i-interphase, i-mitosis, i-cytokinesis ne-G0. Ngasinye salezi zigaba sinezici ezithile nemisebenzi, futhi ndawonye ziqinisekisa ukukhula nokuphindaphindeka kwamaseli okufanele.
1. Isixhumi esibonakalayo
I-Interphase yakha isigaba eside kunazo zonke somjikelezo weseli futhi ihlukaniswe yaba izigaba ezintathu: G1, S kanye ne-G2. Ngesikhathi se-interphase, ingqamuzana lilungiselela ukwehlukana futhi lenze imisebenzi ebalulekile njengokukhula nokuphindaphindeka kwezakhi zofuzo. Izici eziyinhloko zesigatshana ngasinye zichazwe ngezansi:
- G1: Iseli liyalulama kusukela ekuhlukaneni kwangaphambilini, usayizi walo uyakhula futhi amaprotheni adingekayo kumjikelezo weseli ayahlanganiswa.
- S: Ukuphindaphinda kwe-DNA kwenzeka, kukhiqiza ikhophi enembile yezinto zofuzo.
- G2: Iseli lilungiselela ukwehlukana ngemva kokuphindwaphindwa kwe-DNA, amaprotheni ayahlanganiswa futhi ubuqotho bempahla yofuzo buqashwe.
2. I-Mitosis
I-Mitosis yisigaba lapho i-nucleus yeseli ihlukana ibe ama-nuclei amabili afanayo. Lesi sigaba sakhiwe ama-subphase amane: i-prophase, i-metaphase, i-anaphase ne-telophase. Ngesikhathi se-mitosis, ama-chromosome ayajiya futhi aqondanise endizeni yenkabazwe ngaphambi kokuba ahlukane abheke ezigxotsheni zeseli. Ekupheleni kwalesi sigaba, kutholakala amangqamuzana amantombazane amabili anezakhi zofuzo ezifanayo.
3. I-Cytokinesis ne-G0
I-Cytokinesis yisigaba lapho ukuhlukaniswa kwezingxenye ze-cytoplasmic kuqedwa. Ezakhiweni ezitholakala ku-unicellular, i-cytokinesis iphumela ekwakhekeni kwamaseli amantombazane amabili azimele. Ngakolunye uhlangothi, ezintweni eziphilayo ezinamangqamuzana amaningi, lesi sigaba singahluka kuye ngokuthi uhlobo lweseli oluhilelekile. Ekugcineni, isigaba se-G0, esaziwa nangokuthi isigaba sokuphumula, simele isimo lapho amaseli ephuma kumjikelezo weseli futhi ahlale esigabeni esithule kuze kube yilapho ethola umfutho owanele wokubuyela ku-interphase.
Ukubaluleka kokulawulwa komjikelezo wamaseli
Ukulawulwa komjikelezo wamaseli kuyinqubo ebalulekile yokusebenza kahle nokuthuthukiswa kwezinto eziphilayo. Ingqamuzana ngalinye liba nomjikelezo wamangqamuzana ohlanganisa izigaba ezihlukene, njenge-interphase ne-mitosis, okufanele ilawulwe ngokunembile ukuze kugwenywe ukwanda kwamangqamuzana okungalawuleki futhi kuvinjwe izifo ezinjengomdlavuza.
Kunezindlela eziningana ezihilelekile ekulawuleni umjikelezo wamaseli, njengeprotein kinases, ama-cell cycle inhibitors, kanye nezici zokukhula. Lezi zingxenye zakha inethiwekhi eyinkimbinkimbi yokusayina elawula ukuqhubeka kwamaseli ngezigaba ezihlukene zomjikelezo. Isibonelo, ama-protein kinases asebenza njengamaswishi avula noma avale imicimbi yomjikelezo weseli engukhiye, njengokuphindaphinda kwe-DNA nokuhlukaniswa kwe-chromosome ngesikhathi se-mitosis.
Ukugcina ukulawulwa okufanele komjikelezo wamaseli kubalulekile ukuze kuqinisekiswe impilo nokusebenza kahle kwezicubu nezitho zomzimba. Uma kwenzeka amaphutha kule nqubo, njengokulawula okungalungile noma ukuhlukaniswa kwamaseli okungalawuleki, izifo ezimbi zingavela. Umdlavuza, isibonelo, uwumphumela wokwanda okungalawuleki kwamangqamuzana, ngenxa yokuguqulwa kofuzo noma ukwehluleka kwezinqubo. ukulawula umjikelezo weseli.
Inqubo yokuphindaphinda i-DNA
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Ukuphindwaphindwa kwe-DNA, okubuye kwaziwe ngokuthi i-DNA replication, kuyinqubo eyisisekelo eyenzeka kuwo wonke amangqamuzana aphilayo. Phakathi nale nqubo, izakhi zofuzo eziqukethwe ku-DNA ziyakopishwa ukuze kuhlinzekwe umfanekiso ofanayo. Ukuphindaphinda kwe-DNA kwenzeka ku-nucleus yamaseli e-eukaryotic kanye ne-cytoplasm yamaseli e-prokaryotic.
Iyini inhloso yokuphindaphindwa kwe-DNA? Ukuphindaphinda kwe-DNA kubalulekile ekukhiqizeni amangqamuzana kanye nokudluliswa kolwazi lofuzo kusuka kwesinye isizukulwane kuya kwesinye. Ngaphandle kwale nqubo, amaseli awakwazanga ukuhlukana futhi izinto eziphilayo azikwazanga ukukhula noma ukukhula. Ngaphezu kwalokho, ukuphindaphinda kwe-DNA kuyindlela yokulungisa, njengoba kusivumela ukuthi silungise amaphutha okungenzeka ngesikhathi sokuphindaphinda.
Ukuphindaphinda kwe-DNA kulandela uchungechunge lwezinyathelo ezinembayo ezihlanganisa ukuhlukaniswa kwemicu ye-DNA, ukuhlanganiswa kwemicu emisha ehambisanayo, nokuhlanganiswa kwemicu esanda kwakhiwa. Inqubo iqala ngokuchithwa kwe-DNA double helix ngama-enzyme abizwa ngokuthi ama-helicase. Ama-enzyme e-Polymerase abe esebopha emicu ye-DNA ehlukanisiwe futhi aqale ukuhlanganisa imicu emisha ehambisanayo, esebenzisa imicu ekhona njengesifanekiso. Ekugcineni, i-DNA ligase inesibopho sokuhlanganisa imicu esanda kuhlanganiswa, ngaleyo ndlela yakhe ama-molecule amabili afanayo e-DNA.
Isigaba se-G1: ukulungiselela ukuphindaphindwa kwe-DNA
Isigaba se-G1 somjikelezo weseli sibalulekile ekulungiseleleni iseli ukuphindaphinda kwe-DNA. Phakathi nalesi sigaba, ingqamuzana liba nesikhathi sokukhula futhi lenze imisebenzi ehlukahlukene ye-metabolic ukuze kuqinisekiswe ukuthi selikulungele ukuhlanganisa amakhophi anembile ezakhi zalo zofuzo. Ngezansi ezinye zezici ezibalulekile zesigaba se-G1:
Ukuqoqwa komsoco: Phakathi nesigaba se-G1, ingqamuzana ligxila ekumunceni nasekugcineni imisoco edingekayo kunqubo yokuphindaphinda kwe-DNA. Lokhu kuhlanganisa ukumuncwa kwe-glucose, ama-amino acid namanye ama-molecule abalulekile ukuze kuhlanganiswe izakhi ze-DNA.
Ukwenziwa kwamaprotheni: Isigaba se-G1 yisikhathi somsebenzi oqinile wokwenziwa kwamaprotheni. Ingqamuzana likhiqiza amaprotheni ahlukahlukene adingekayo ukuze kulungiswe indawo efanele yokuphindaphinda kwe-DNA. Lawa maprotheni ahlanganisa izici zokuloba kanye nama-enzyme ahilelekile ekuphindaphindeni kwe-DNA.
Ukulawula umjikelezo weseli: Phakathi nesigaba se-G1, iseli lihlola ngokucophelela ubuqotho bezinto zalo zofuzo futhi lihlole noma yimuphi umonakalo noma amaphutha ku-DNA ekhona. Uma kutholwa okungavamile, iseli lingamisa inqubo yokuphindaphinda i-DNA futhi liqalise izindlela zokulungisa noma ekugcineni livule i-apoptosis, inqubo ukufa kweseli ehlelelwe ukuvimbela ukusakazeka kolwazi lofuzo oluyiphutha.
Isigaba S: I-DNA synthesis
Esigabeni sika-S somjikelezo weseli, owaziwa nangokuthi isigaba sokuhlanganiswa kwe-DNA, inqubo ebalulekile yokuphindaphinda kwezinto zofuzo iyenzeka. Phakathi nalesi sigaba, i-DNA iyaphindwa ukuze yenze amakhophi amabili anembile, iqinisekisa ukuthi ingqamuzana ngalinye lendodakazi lithola ukwaziswa okuphelele kofuzo. Isigaba S sibalulekile ekukhuleni nasekuthuthukisweni kwezinto eziphilayo, njengoba siqinisekisa ukwethembeka nokuzinza kwe-genome.
Phakathi nesigaba sika-S, umshini wamaselula uyacushwa futhi uqale ukusebenza ekuphindaphindeni kwe-DNA. Le nqubo yenziwa ngendlela ye-semiconservative, okusho ukuthi umucu wokuqala ngamunye we-DNA usebenza njengesifanekiso sokuhlanganisa umucu omusha ohambisanayo. Ukuphindaphinda kwenziwa ngendlela ehlelekile nenembayo, ngenxa yochungechunge lwama-enzyme akhethekile namaprotheni asebenza ndawonye.
Ukuze kuzuzwe ukuphindaphinda okuphumelelayo, i-DNA kufanele ikhululwe futhi ihlukaniswe ibe imicu ngayinye. I-enzyme ebizwa ngokuthi i-helicase idlala indima ebalulekile kule nqubo, njengoba inesibopho sokuphula izibopho ze-hydrogen phakathi kwezisekelo ze-nitrogen nokuqaqa i-double helix. Amaprotheni abopha i-DNA abe esebophezela emicu eveziwe ukuze awahlukanise futhi awavimbele ukuthi ahlangane futhi. Lokhu kuvumela i-DNA polymerase, i-enzyme enesibopho sokuhlanganisa umucu omusha we-DNA, ukuthi ijoyine isifanekiso futhi iqale ukwengeza ama-nucleotide ahambisanayo. Ngale ndlela, kwakheka imicu emibili ye-DNA efana neyokuqala.
Isigaba se-G2: ukulungiselela ukuhlukaniswa kwamaseli
Isigaba se-G2 yisigaba esibalulekile emjikelezweni weseli lapho amaseli elungiselela ukuhlukana bese enza amaseli amantombazane amabili. Phakathi nalesi sigaba, uchungechunge lwezenzakalo eziyisisekelo zenzeka eziqinisekisa ukuthi inqubo yokuhlukaniswa kwamaseli yenziwa ngendlela efanele futhi ngaphandle kwamaphutha.
Okokuqala, phakathi nesigaba se-G2, ukuhlanganiswa kwamaprotheni kanye ne-RNA edingekayo esinyathelweni esilandelayo sokuhlukaniswa kwamaseli kwenzeka. Lokhu kuhilela ukuphindwaphindwa kanye nokukhiqizwa kwama-enzyme abalulekile nama-molecule ayodingeka ekuphindaphindeni kwezinto zofuzo esigabeni esilandelayo. Ngaphezu kwalokho, amaseli aphinde enze isheke eliqinile le-DNA yawo ukuze aqinisekise ukuthi akukho monakalo noma ukuguqulwa okungathinta ukuqina kofuzo lwamaseli endodakazi.
Esinye isici esibalulekile sesigaba se-G2 ukulungiswa kwama-microtubules e-cytoskeleton ukuze kuhlukaniswe amaseli. Phakathi nalesi sigaba, ama-microtubules ahlelwa futhi alungiselelwe ukwenza i-mitotic spindle, isakhiwo esibucayi sokuhlukaniswa okulungile kwama-chromosome ngesikhathi sokuhlukaniswa kwamaseli. Ukwengeza, ukuphindaphinda nokusatshalaliswa kwama-organelles amaselula, njenge-mitochondria kanye ne-endoplasmic reticulum, kwenzeka ukuze kuqinisekiswe ukuthi amangqamuzana endodakazi anazo zonke izakhi ezidingekayo ukuze enze imisebenzi yawo. imisebenzi yayo ngokufanele.
Isigaba se-M: i-mitosis kanye nokuhlukaniswa kwamaseli
Isigaba esingu-M siyisigaba esibalulekile kumjikelezo weseli, lapho ingqamuzana lomama lihlukana libe amaseli amantombazane amabili afanayo. Lesi sigaba sihlukaniswe ngezinqubo ezimbalwa ezihambisana kakhulu: i-mitosis ne-cytokinesis. Lezi zinqubo zivumela ukusatshalaliswa okufanele kwezakhi zofuzo kanye nokuqukethwe kwe-cytoplasmic phakathi kwamaseli endodakazi ewumphumela.
I-Mitosis iyinqubo eyinhloko yesigaba se-M futhi yona ngokwayo ihlukaniswe ngezigaba ezimbalwa ezibalulekile. Lezi zigaba zihlanganisa i-prophase, i-metaphase, i-anaphase, ne-telophase. Ngesikhathi se-prophase, ama-chromosome abonakalayo ayajiya futhi amafomu e-mitotic spindle, okuvumela ukuthwebula nokunyakaza kwama-chromosome ngama-microtubules. Ku-metaphase, ama-chromosome aqondana endizeni yenkabazwe, kuyilapho ku-anaphase, ama-chromosome angudade ayahlukana futhi adlulele ezigxotsheni eziphambene zeseli. Ekugcineni, ku-telophase, ama-chromosome ayancipha futhi ulwelwesi olusha lwenuzi luzungeze iqoqo ngalinye lama-chromosome.
I-Cytokinesis inqubo ehambisanayo ku-mitosis efinyelela umvuthwandaba ngokuhlukana ngokomzimba kwamangqamuzana amantombazane. Lokhu kwenzeka ngokwakhiwa kweringi yenkontileka eyakhiwe ngamaprotheni e-myosin kanye ne-actin endaweni ye-equatorial yeseli. Le ndandatho ifinyela kancane kancane, ihlukanise ingqamuzana likamama libe amangqamuzana amantombazane amabili ahlukene. I-Cytokinesis ingahluka kuye ngohlobo lweseli nezinto eziphilayo ezihilelekile, futhi iyingxenye ebalulekile yokwakheka okufanele kwezicubu nezitho ngesikhathi sokuthuthukiswa.
Izindawo zokuhlola nokulawula umjikelezo wamaseli
Umjikelezo wamaseli uyinqubo elawulwa kakhulu eqinisekisa ukuphindwaphindwa okulungile nokusatshalaliswa kwezinto zofuzo. Ukuqinisekisa ubuqotho be-DNA futhi kuvinjwe ukwanda kwamaseli alimele noma amaseli anokuguqulwa kofuzo, izindlela zokulawula ezaziwa ngokuthi izindawo zokuhlola zenziwe.
Izindawo zokuhlola ze- cell umjikelezo kukhona izindawo zokuhlola ezibalulekile ezigabeni ezahlukene zomjikelezo. Lezi zindawo zokuhlola zinesibopho sokuqinisekisa ubuqotho be-DNA, ukuphindaphinda okulungile kwama-chromosome kanye nokuhleleka okufanele kwama-microtubules. Uma kutholwa okungavamile kunoma iyiphi yalezi zinqubo, izindawo zokuhlola zingamisa okwesikhashana ukuqhubeka komjikelezo weseli ukuze zivumele ukulungiswa komonakalo noma, ezimweni ezingalungiseki, zenze i-apoptosis iqede iseli.
Kunezindawo zokuhlola ezintathu eziyinhloko kumjikelezo weseli: indawo yokuhlola ye-G1, indawo yokuhlola ye-G2 kanye nendawo yokuhlola ye-metaphase. Endaweni yokuhlola i-G1, kuyaqinisekiswa ukuthi i-DNA isesimweni esihle futhi isesimweni esifanele sokuphindaphinda. Endaweni yokuhlola i-G2, kuyabhekwa ukuthi ingabe zonke izinyathelo zokuphindaphinda i-DNA seziqediwe nokuthi awekho yini amaphutha kuma-chromosome. Ekugcineni, indawo yokuhlola i-metaphase ihlola ukuqondanisa okulungile kwama-chromosome ku-spindle ye-mitotic ngaphambi kokuhlukaniswa kwama-chromatid odade ngesikhathi se-anaphase.
Ukulawulwa komjikelezo wamaseli nokuvimbela umdlavuza
Ezakhiweni zamangqamuzana amaningi, ukulawulwa komjikelezo wamaseli kuyinqubo ebalulekile yokugcina ubuqotho be-genomic nokwanda kwamaseli. Le nqubo eyinkimbinkimbi iqinisekisa ukuthi amangqamuzana ahlukana ngendlela elawulwayo futhi enembile, evimbela ukuthuthukiswa kwezifo ezifana nomdlavuza.
Ukulawulwa komjikelezo weseli kuhilela uchungechunge lwezindawo zokuhlola, lapho kuhlolwa khona ukuthi ingabe amaseli asiqede kahle isigaba ngasinye ngaphambi kokudlulela kwesilandelayo. Lezi zindawo zokuhlola zisebenza njengabanakekeli bobuqotho be-genome, ezimisa ukuqhubeka komjikelezo weseli uma kutholwa okungavamile kwe-DNA, amaphutha okuphindaphinda noma ukulimala kwekhromosome. Uma kutholakala okungahambi kahle, amaseli avula izindlela zokulungisa noma angakwazi ngisho nokwenza i-apoptosis, ukufa kweseli okuhleliwe, ukuvimbela ukwanda kwamaseli awonakele.
Ukuvimbela umdlavuza kusekelwe ekulawuleni okusebenzayo komjikelezo wamaseli. Uma le nqubo isebenza kahle, amangqamuzana alimele noma ashintshwe izakhi zofuzo ayasuswa ngaphambi kokuba ande futhi akhe izimila eziyingozi. Kodwa-ke, kwezinye izimo, amaseli angaqongelela ukuguqulwa kwezakhi ezivala izindlela zokulawula umjikelezo wamaseli, okuvumela ukuphindaphinda okungalawuleki nokungalawuleki.
Ukuguqulwa komjikelezo wamaseli nemiphumela yawo
Ukuguqulwa komjikelezo wamaseli izinguquko ezingavamile enqubweni yokuhlukaniswa kwamaseli, okungaba nemiphumela emibi kakhulu emzimbeni. Lezi zinguquko zingenzeka ngenxa yokuguquka kwezakhi zofuzo ezinesibopho sokulawula umjikelezo weseli, ukulimala kwezakhi zofuzo noma ukungalingani kumasignali alawula umjikelezo. Lapho umjikelezo weseli uthinteka, kungase kuvele imiphumela ehlukahlukene ethinta kokubili umuntu kanye nezicubu noma izitho lapho ukuguqulwa kwenzeka khona.
Omunye wemiphumela eyinhloko yokuguqulwa komjikelezo wamaseli ukwakheka kwamathumba. Uma amaseli engakwazi ukulawula kahle ukuhlukana kwawo, angaqala ukuzalana ngokungalawuleki, enze inqwaba yamaseli angavamile. Lezi zixuku, ezaziwa ngokuthi amathumba, zingaba zimbi noma zibe yingozi. Izimila ezinhle azisabalali kwezinye izicubu futhi ngokuvamile aziyingozi kangako. Ngakolunye uhlangothi, izimila eziyingozi zinomdlavuza futhi zingahlasela izicubu eziseduze noma zisakazeke ngegazi noma nge-lymphatic stream, zibangele ama-metastases ezingxenyeni ezihlukahlukene zomzimba.
Ngaphezu kokwakheka kwesimila, ukuguqulwa komjikelezo wamaseli nakho kungadala izifo ezibulalayo zofuzo. Uma amangqamuzana engahlukani ngendlela efanele, ukuphambana kofuzo kungase kwenzeke kubantu abasha. Lokhu kungahambi kahle kungaholela ezifweni zofuzo, ezingaba nemiphumela emibi kakhulu empilweni yabantu abathintekile. Ezinye izibonelo Izifo zofuzo ezibangelwa ukuphazamiseka kokujikeleza kwamaseli zihlanganisa i-Down syndrome, i-cystic fibrosis kanye ne-hemophilia.
Izincomo zokugcina umjikelezo wamaseli onempilo
Amathiphu okugcina umjikelezo wamaseli onempilo:
1. Ukusetshenziswa kwe-Antioxidant: Ama-Antioxidant adlala indima ebalulekile ekuvikeleni amangqamuzana ethu ekucindezelekeni kwe-oxidative, into eyaziwa ngokulimaza i-DNA futhi ikhuthaze ukuguga kwamaselula. Qinisekisa ukuthi ufaka ukudla okunothe nge-antioxidant ekudleni kwakho, njengezithelo nemifino enemibala egqamile, imbewu, namantongomane.
2. Gwema ukucindezeleka okungapheli: Ukucindezeleka okungapheli kungaba nomthelela omubi kumjikelezo wethu wamaseli. Zama ukuthola izindlela ezisebenzayo zokulawula ukucindezeleka, njengokuzijwayeza izindlela zokuphumula, izivivinyo zokuphefumula, noma imisebenzi oyithandayo, njengokufunda, ukudweba, noma ukulalela umculo.
3. Gcina ukudla okunomsoco: Ukudla okulinganiselayo kubalulekile ukuze ugcine umjikelezo wamangqamuzana onempilo. Qiniseka ukuthi uthola amaprotheni anele, amavithamini namaminerali. Gwema ukweqisa kushukela ocolisisiwe, amafutha agcwele kanye nokudla okugayiwe kakhulu, njengoba kungabangela ukuvuvukala futhi kulimaze amangqamuzana ethu.
Imibuzo Nezimpendulo
Q: Uyini umjikelezo weseli futhi uyini ukubaluleka kwawo?
A: Umjikelezo weseli inqubo amaseli adlula kuyo ukuze akhule futhi ahlukane abe amaseli amantombazane amabili afanayo. Kubalulekile ekuthuthukisweni nasekukhuleni kwezinto eziphilayo, kanye nokuvuselelwa kwezicubu kanye nokulungiswa kwamaseli awonakele.
Q: Yiziphi izigaba zomjikelezo weseli?
A: Umjikelezo wamaseli uhlukaniswe izigaba ezine eziyinhloko: i-G1 noma isigaba sokukhula 1, isigaba sika-S noma ukuhlanganiswa kwe-DNA, i-G2 noma isigaba sokukhula sesi-2, kanye nesigaba esingu-M noma i-mitosis.
Q: Kwenzekani esigabeni se-G1 somjikelezo weseli?
A: Phakathi nesigaba se-G1, iseli liyakhula futhi lilungiselele isinyathelo esilandelayo somjikelezo. Iphinde yenza imisebenzi ehlukahlukene ye-metabolic futhi ihlanganise amaprotheni adingekayo ekuthuthukisweni kwayo.
Q: Kwenzekani esigabeni sika-S somjikelezo weseli?
IMP: Esigabeni sika-S, ingqamuzana liphindaphinda i-DNA yalo, okungukuthi, lihlanganisa ikhophi elinembile lezakhi zalo zofuzo. Lokhu kuqinisekisa ukuthi womabili amangqamuzana endodakazi atholakalayo anesethi efanayo yemiyalo yofuzo.
Q: Iyini inhloso yesigaba Umjikelezo wamaseli we-G2?
A: Phakathi nesigaba se-G2, iseli liyaqhubeka nokukhula futhi lilungiselela ukuhlukaniswa kwamaseli. Ubuqotho be-DNA esanda kuhlanganiswa buyaqinisekiswa futhi amaphutha okungenzeka noma umonakalo uyalungiswa.
Q: Siyini isigaba se-M somjikelezo weseli?
A: Isigaba esingu-M, noma i-mitosis, yilapho kwenzeka khona ukuhlukana kwamaseli. Iseli lihlukana libe amaseli amantombazane amabili afanayo, ngalinye linekhophi ephelele nenembile yezakhi zofuzo.
Q: Ingabe zikhona izigaba ezengeziwe kumjikelezo weseli?
IMP: Ngaphezu kwezigaba ezine ezishiwo, kunesigaba esibizwa nge-G0, lapho amaseli asesimweni sokuphumula noma ukungande. Amanye amaseli angangena kulesi sigaba okwesikhashana noma unomphela, ngaphandle kokuqhubeka nomjikelezo weseli.
Q: Ulawulwa kanjani umjikelezo weseli?
IMP: Umjikelezo wamaseli ulawulwa ngokuqinile uchungechunge lwamaprotheni nezici zokulawula eziqinisekisa ukuthi isigaba ngasinye senzeka ngesikhathi esifanele nangendlela ehlelekile. Lezi zindlela zokulawula zivimbela ukukhula kwamangqamuzana okungalawuleki kanye nokwakheka kwamaseli angavamile.
Q: Kwenzekani uma kukhona izinguquko kumjikelezo weseli?
IMP: Ukushintsha komjikelezo wamaseli kungaholela ezifweni ezinjengomdlavuza. Lapho izindlela zokulawula zingaphumeleli, amangqamuzana anganda ngokungalawuleki futhi akhe izimila eziyingozi.
Q: Iluphi ucwaningo olwenziwayo mayelana nomjikelezo weseli?
IMP: Ucwaningo ngomjikelezo wamaseli lukhulu futhi luyaqhubeka. Njengamanje, kwenziwa ucwaningo ukuze kutholakale abalawuli abasha bomjikelezo weseli, kanye nokuthuthukisa izindlela zokwelapha ezihloselwe ukuphazamiseka kwamaselula nezifo ezihlobene.
Ekuphetheni
Kafushane, umjikelezo wamaseli uyinqubo ebalulekile evumela ukukhula nokwehlukana kweseli ezintweni eziphilayo. Yakhiwe uchungechunge lwezigaba, ngasinye sinomsebenzi othile futhi silawulwa yizinqubo eziyinkimbinkimbi ze-biochemical. Iqala ngesigaba se-G1, lapho ingqamuzana likhula futhi lilungiselela ukuphindwaphindwa kwe-DNA yayo esigabeni sika-S Khona-ke, esigabeni se-G2, iseli lilungiselela ukuhlukaniswa kwamaseli esigabeni esingu-M, esihlanganisa i-mitosis ne-cytokinesis. Lezi zigaba zilawulwa ngokucophelela ngamaprotheni nezici zokulawula, ngaleyo ndlela kuqinisekiswe ukukhiqizwa kwamangqamuzana okunembayo nangempumelelo. Ukuqonda umjikelezo wamaseli kubalulekile ocwaningweni lwesayensi nolwezokwelapha, futhi kungaholela ekuthuthukisweni kwezokwelapha umdlavuza nezifo ezihlobene nokuhlukaniswa kwamaseli okungalawuleki. Njengoba sithuthukisa ukuqonda kwethu umjikelezo weseli, singavula imininingwane emisha ezozuzisa kokubili impilo yomuntu kanye nesayensi yezinto eziphilayo jikelele.
Ngingu-Sebastián Vidal, unjiniyela wekhompyutha ozifelayo ngobuchwepheshe kanye ne-DIY. Ngaphezu kwalokho, ngingumdali we tecnobits.com, lapho ngabelana khona ngezifundo zokwenza ubuchwepheshe bufinyeleleke kakhudlwana futhi buqonde wonke umuntu.