Joang fission ea nyutlelie? fission Types

Mong le e mong seleng ea qala bophelo ba eona ha a arohana le motsoali, le qetella ho ba, a le fa monyetla oa ho hlaha liseleng tsa bona morali. Nature feela tsela e fetang e mong oa ho arola ea mantlha, ho itšetlehile ka sebopeho bona.

Mekhoa ea ho karohano seleng ea

Arola ea mantlha e itšetlehile ka mofuta seleng ea ka :

- binary fission (fumanoang ka prokaryotes).

- amitosis (tsela e tobileng karohano).

- Mitosis (tloaelehile eukaryotes).

- Meiosis (bakeng sa ho arola liseleng tse kokoana-hloko).

Mefuta fission ikemiselitse ka tlhaho le ho dumellana le sebopeho ea sele le mosebetsi ho o etsa ka macroorganism kapa ke ka boeona.

binary fission

Hangata ka ho fetisisa mofuta ona o fumanoa lisele tse prokaryotic. Ho na le ka palopedi le chitja DNA molek'hule. Binary fission ea khubung e joalo e bitsoang ka lebaka la tsona seleng e 'mè ho na le ba babeli ba ka tsela e tsoanang boholo bo lekaneng morali.

Ka mor'a taba liphatsa tsa lefutso (DNA kapa RNA molek'hule) le lokisitsoeng e loketseng, i.e. e imenne habeli, ho tloha leboteng seleng ea qala ho ba le ho dia ho parola, e leng e butle-butle tapered le cytoplasm arola likarolo tse peli tse ka bang lekanang.

Bobeli fihla moo ho arohanang thulaganyou e bitswang megagametophyte kapa lekane binary fission. Tabeng ena, marako seleng ea hlaha protrusion karolo, e leng e butle-butle ho hōla. Ka mor'a hore "liphio" le boholo ba tsona seleng e 'mè e tla lekana, ba arohane. karolo e itseng ea lerako seleng ea e tsa maiketsetso hape.

amitosis

Sena se arola khubung ea tšoanang le a hlalositsoeng ka holimo, le phapang hore ha ho na palopedi ya lintho tse bonahalang tse liphatsa tsa lefutso. Mokhoa ona o ne a pele a hlalosa ka ho Remak setsebi sa baeloji. ketsahalo ena e hlaha ka lisele tse pathologically fetoloa (bolaeang phetoho), 'me ke ntho e tloaelehileng fisioloji bakeng sa sebete dinama tse nyenyane tse, lefufuru le cornea.

tshebetso e bitsoa ntoa ea nyutlelie fission amitosis hobane sele e lule e mosebetsi oa eona, 'me ha a lahleheloa ke e le nakong mitosis. Sena se hlalosa hore na thepa e sa tloaelehang tse amanang le tsamaiso e karohano seleng. Ho phaella moo, ka ho toba karohano konokono fetisa ntle leakage radiation, kahoo morali lisele tse chromatin e ajoa ho lumellanang. Ka tse latelang, lisele tse joalo ka ho sebelisa potoloho ea mitotic. Ka linako tse ling, ka lebaka la amitosis thehoa lisele tse multinucleated.

mitosis

Sena se sa tobang ea nyutlelie fission. Hangata ka ho fetisisa e fumanoang liseleng tse eukaryotic. Phapang e khōlō ea sena itšetlehile ka 'nete ea hore ngoana le lisele tse mè na le palo e tšoanang ea chromosomes. Ka hona 'mele o tšehetsoa ka palo hlokahala lisele tse, hammoho le khoneha nchafatso le kgolo ya dithulaganyo. The mitosis pele ka seleng ea phoofolo e hlalositswe Flemming.

Tsela ea ho arola khubung tabeng ena e arohane ka ho toba ka interphase le mitosis. Interphase - boemo ba lisele tsa tsona li lula pakeng tsa likarohano. Ho khona ho khetholla mekhahlelo e 'maloa:

1. presynthetic nako - seleng e ntse e hōla, ho bakoang ke liprotheine le lik'habohaedreite, e ka mafolofolo tsa maiketsetso ATP (adenosine diphosphate).

2. maiketsetso nako - ka lintho tse bonahalang le liphatsa tsa lefutso e imena habeli.

3. postsynthetic nako - likarolo lisele li imenne habeli, ho na le liprotheine tse etsang fihla moo ho arohanang leakage radiation.

The mekhahlelo e sa mitosis

Karolo ea khubu ea lisele eukaryotic - tshebetso eo e hlokahalang bakeng sa sebopeho sa organelles e eketsehileng - centrosomes. E haufi le khubung ea, 'me mosebetsi-holo ke ho theha organelles ntjha - leakage radiation. sebopeho sena se ba thusa ho evenly aba chromosomes pakeng tsa lisele tse morali.

Ho na le mekhahlelo e mene ea mitosis:

1. Prophase: chromatin ka khubung ea condenses ka chromatids, e leng ke haufi le centromeres eang ka bobedi ya ho theha chromosomes. Nucleoli qhala, ba qhalakanyetsa ho lipalo tsa centrioles seleng ea ka. Thehoa karohano leakage radiation.

2. Metaphase: chromosomes a lokisetsa ka mola feta bohareng ba seleng ea ho theha ka poleiti metaphase.

3. Anaphase: chromatids diverge tloha bohareng seleng ea ikutloeleng lipalo tse, 'me joale arotsoe ka tse peli tse centromere. mokhatlo oa sena se ka etsahala ka lebaka la karohano leakage radiation, le dikgwele ba tsona li fokotsehile 'me a otlolla chromosomes ka litaelo tse sa tšoaneng.

4. Telophase: thehoa morali nuclei. Chromatids hape fetoha chromatin, khubung ea thehoa, 'me ho eona - ea nucleoli. E fella ka tsohle petsoha ha cytoplasm le leboteng seleng ea sebopeho.

endomitosis

Keketseho ea lintho tse bonahalang tse liphatseng tsa lefutso, e leng ha e fane ka bakeng sa karohano ea khubu ea bitsoang endomitosis. E fumanoa lisele tsa limela le liphoofolo. Tabeng ena ho na le ho na timetso ea cytoplasm le khubung lera, empa e ba chromatin ka chromosomes, ebe dispiralized.

Tshebetso ena e dumella ho fumana polyploid khubung moo dikahare DNA e eketseha. Joalo kolone eaba ba etsa lisele tse fumanoang ka lesapo moko. Ho phaella moo, ho na le maemong a mang, ha DNA molek'hule e imenne habeli, 'me palo ea chromosomes sa ntse e le' ngoe. Ba tsejoa e le polythene, 'me ba ka ba fumanang liseleng likokoanyana.

e bolelang mitosis

Mitotic arola khubung ea - e le tsela ea ho lula re ena le sete kamehla chromosomes. lisele tse morali na le sete e tšoanang ea liphatsa tsa lefutso e le motsoali ea se nang 'me kaofela ha litšobotsi tlholeho ho eona. Mitosis e hlokehang bakeng sa:

- kgolo le ntshetsopele ya phelang multicellular (ho tloha ka logan ea lisele kokoana-hloko);

- displacement tsa le dikarolo seleng e ka tlaase ho e ka holimo le Phetolo lisele tsa mali (erythrocytes, leukocytes, li-platelet);

- ho lokisa senyehile dinama tse nyenyane tse (ka bang liphoofolo matla a ho nchafatso e E le hore bakeng sa ho pholoha, tse kang starfish le mekholutsoane);

- diplobiont ea limela le ba bang ba liphoofolo tse (invertebrates).

meiosis

arola kokoana-hloko le ka liseleng tsa mochine nuclei fapane batla ho tloha somatic. Ka lebaka leo, o ile a fumana lisele tse nang le halofo tlhahisoleseding liphatsa tsa lefutso ho feta pele ho tsa bona. Sena ke hlokahala e le hore ho ba le nomoro ea kamehla ea chromosomes ka 'ngoe a ka cell ea' mele.

Meiosis le hlaha ka mekhahlelo e 'meli:

- Phokotso sethaleng;

- equational sethaleng.

Tšoanetseng nakong tshebetso ke khoneha feela ka lisele tse ka esita le palo ea chromosomes (diploid phase, tetraploid, le geksaproidnym sa t. D.). Ya e le hantle, e sala e ho bonolo ho feta meiosis le lisele tse ka makatsa sete ya chromosomes, empa ka nako eo bana ba ka 'na se ke ua solofetsang.

mochine ona ho etsa bonnete ba nyopa manyalong interspecific. Ho tloha ka kokoana-hloko lisele tse disete e fapaneng ya chromosomes, ho di raraanyang go logan ea bona 'me ponahalo ea bana ba solofetsang le e nonneng.

Karolo ea pele ea meiosis

mohato pheta taba ka ho lebitso la ba mitosis: prophase, metaphase, anaphase, telophase. Empa ho na le ba bang ba se tšoane bohlokoa.

1. Prophase: habeli sete ya chromosomes etsa letoto la lengths, feta methati e mehlano (leptotena, zygotes, Paquita, diplotene, diakinesis). Ho na le leboha ena kaofela ho conjugation le tšela-fetang.

Conjugation - sena convergence tsa chromosomes homologous. Ka leptotene therebetween theha linaleli tšesaane ebe kopanele chromosome lipara zygotene le lebaka fumanoa ka sebōpeho sa chromatids bane.

Phetoho - tshebetso ea sefapano-dikarolo tsa phapanyetsano pakeng chromatids ausi oa kapa chromosomes homologous. Hlahellang ka sethaleng pachytene. mateanong a litsela thehoa (chiasm) chromosomes. Ho batho, fapanyetsana tsena e ka ba pakeng tsa mashome a mararo a metso e mehlano ho tse mashome a tšeletseng a metso e tšeletseng. Le ka lebaka la mokhoa ona ke heterogeneity liphatsa tsa lefutso tsa sephetho le lintho tse bonahalang, kapa a iponahatsa diretswe go dira gametes.

Ha ho na le fihla e sethaleng diplotene tsa chromatids mane mehahong timetsoa le khaitseli ea chromosomes vzaimoottalkivayutsya. Diakinesis tlatsang phetoho ea ho tloha prophase ho metaphase.

2. Metaphase: chromosomes Teng fihlela haufi le equator ea sele.

3. Anaphase: chromosomes, a ntse a e entsoeng ka chromatids pedi diverge ho lipalo ka seleng.

4. Telophase: arola leakage radiation bo felisoe, ho fellang ka ho thehoa ea lisele tse peli le sete haploid tsa chromosomes le habeli palo ea DNA.

Bobeli meiotic karohano

Mokhoa ona o boetse o bitsoa "mitosis, meiosis." Ka motsotso oo o pakeng tsa mekhahlelo e pedi DNA kopitsa ha ke sa etsahala, 'me seleng ea bobeli kena prophase ea sete o tšoanang oa ho chromosomes, eo o ile a lula ka mor'a 1 telophase.

1. Prophase: chromosomes condense makhalong setsi sa karohano seleng ea (bakiloeng lona ho fapana lipalo ea sele), le selateng sa liha khubung thehoa karohano leakage radiation e ratang perpendicular ho leakage radiation tsa karohano pele.

2. Metaphase: chromosomes ba sebakeng equator, Ho thehoa metaphase poleiti.

3. Anaphase: chromosomes ba arotsoe ka chromatids hore ekongengisa ka 'nģa tsohle.

4. Telophase: liseleng morali thehoa chromatids konokono dispiralized ka chromatin.

Qetellong ba mohato oa bobeli oa sele le 'ngoe motsoali, re na le ka tiasa yona e mene le halofo sete ea chromosomes. Ha meiosis etsahala ka kopanelo le moleng kokoana-hloko (ke hore, sebopeho sa lisele tse ho kopanela liphate), karohano ke sharply lekane, 'me Ho thehoa ke seleng e le' ngoe le sete haploid tsa chromosomes 'me tse tharo phokotso namane, ha ba jereng hlokahala lesedi liphatsa tsa lefutso. Ba ho hlokahala hore ho etsa bonnete ba hore ka lehe le peō ea botona lula feela halofo ea lintho tse bonahalang le liphatsa tsa lefutso tsa sele motsoali. Ho feta moo, ka foromo ena ea karohano ea nyutlelie e fana ka ponahalo ea tlhakantsuke mocha oa liphatsa tsa lefutso, hammoho le lefa la bo hloekileng ba alleles.

Ka phetolelo ea bonolo ea meiosis teng ha ho na le bareng e 'ngoe feela ka mohato oa pele,' me ka bobeli ho na le phetoho. Bo-rasaense ba nahana hore ho ka foromo ena ke selelekela ho iphetola ha lintho ba tloaelehileng meiosis phelang multicellular. Mohlomong ho na le litsela tse ling tsa fission nyutlelie, tseo bo-rasaense ba e-s'o tsebe.