Fission yenyukireya sei? fission Types

Sero rimwe nerimwe kunotanga upenyu hwayo kana aparadzana mubereki, uye anoguma ava, achipa mukana kuoneka kuti mwanasikana muzvitokisi zvavo. Nature akapa nzira inopfuura mumwe kugovera chinoumba, zvichienderana mamiriro avo.

Nzira muchitokisi weboka

Kupatsanura chinoumba kunobva muchitokisi mhando :

- binary fission (anowanikwa prokaryotes).

- amitosis (zvakananga nzira kupesana).

- Mitosis (nevakawanda eukaryotes).

- Meiosis (nokuti kupatsanura utachiona masero).

fission mhando takatsunga ne hunhu uye kunoenderana sechivako sero uye mashandiro nayo anoita mu macroorganism kana woga.

binary fission

Kakawanda izvi mhando inowanikwa mumasero prokaryotic. It kunoratidzwa doubling dzeraundi makavharidzira, morekuru reDNA. Binary fission of musimboti iri atumidzwa nokuda mai sero pane vaviri mwanasikana zvakaenzana kadikidiki.

Pashure magene nyaya (DNA kana RNA Morekuru) wakagadzirirwa maererano, i.e. nayo kaviri, kubva muchitokisi parusvingo anotanga kuumba transverse partition, iyo zvishoma tapered uye cytoplasm rinokamukana huviri anenge kuenzana zvikamu.

Chechipiri panoparadzana muinonzi yotunga kana gogonera binary fission. Panyaya iyi, sero masvingo kuonekwa mugove protrusion, iyo zvishoma kukura. Mushure "itsvo," uye kukura mai sero achava vakaenzana, vari vakaparadzana. A mugove muchitokisi rusvingo iri synthesized zvakare.

amitosis

Boka iri musimboti zvakafanana avo pamusoro apa, pamwe musiyano kuti hapana doubling pakati majini zvinhu. Nzira iyi yakatanga rakarondedzerwa Remak zvipenyu. Izvi zvinoitika mumasero pathologically akachinjwa (akaipa kusanduka), uye ari vasiri wokuyera kuti chiropa rinenge shwashwa uye cornea.

Masero anonzi renyukireya fission amitosis nekuti sero anoramba dzayo basa, uye asingauyi kurasikirwa navo panguva mitosis. Izvi anotsanangura kanganisika ehupfumi chokuita muchitokisi kupesana rikurumidze. Uyezve, zvakananga nokupesana chinoumba rinopfuura pasina chokurukisa, saka mwanasikana masero chromatin ari kuparadzirwa noruvara. Munyaya inotevera, masero kwakadaro havagoni kushandisa mashoko mitotic kutenderera. Dzimwe nguva, somugumisiro amitosis vakaumba masero multinucleated.

mitosis

renyukireya fission ichi zvisina kunanga. Most aiwanzowanika mumasero eukaryotic. The musiyano chikuru izvi iri chokwadi kuti mwana uye masero rwaamai ane chete nhamba okutodza. Kuburikidza ichi muviri rinotsigirwa nezvinoitwa inodiwa nhamba masero, uyewo zvinoita patsva uye kukura kwendangariro. The mitosis kutanga imwe muchitokisi mhuka inorondedzerwa Flemming.

Muitiro kugovera musimboti ichi nyaya iri akaparadzaniswa zvakananga interphase uye mitosis. Interphase - ezvinhu masero vazorore pakati mapoka. Inogona kusiyanisa maitikiro akawanda:

1. presynthetic nguva - sero chichikura, rinoungana mapuroteni uye makabhohaidhiretsi, ari kushingaira synthesized ATP (adenosine triphosphate).

2. chakaita zvokugadzirwa nguva - majini zvinhu kaviri.

3. postsynthetic nguva - the cellular zvinhu zviri kaviri, pane mapuroteni hunoumba panoparadzana chokurukisa.

Maitikiro ose mitosis

Weboka musimboti masero eukaryotic - mumwe mutoo iyo inodikanwa paumbwe kweimwe organelles - centrosomes. Riri pedyo musimboti, uye ayo chikuru basa iri kuumba organelles itsva - chokurukisa. mamiriro Izvi zvinobatsira kuti zvakaenzana kuparadzira okutodza pakati masero mwanasikana.

Pane zvikamu zvina mitosis:

1. Prophase: chromatin ari musimboti condenses iri chromatids, vari pedo centromeres zvinoenda vaviri vaviri kuumbika okutodza. Nucleoli kuiparadza, yokubudisa kuti matanda sero centrioles. Kuvakwa nekupesana chokurukisa.

2. Metaphase: asi okutodza vanosarudzirwa mumutsetse achipfuura nepakati sero kuumba metaphase ndiro.

3. Anaphase: chromatids diverge kubva muchitokisi centre kurutivi mapango, uye ipapo huviri centromere. Bato Izvi zvinobvira nokuti weboka chokurukisa, kuti neshinda ayo ipfupi uye akatambanudza okutodza kwakasiyana-siyana.

4. Telophase: kuumbwa mwanasikana nuclei. Chromatids dzokeraizve kupinda chromatin, musimboti aumbwa, uye zvirimo - the nucleoli. Anopedzisa weboka dzose cytoplasm uye musero rusvingo inotungamirwa.

endomitosis

Kuwedzera majini zvinhu, izvo asingagoveri weboka musimboti, rinonzi endomitosis. It Inowanikwa masero nemhuka. Muchiitiko ichi hapana kuparadzwa cytoplasm uye mwoyo Kamudzira, asi anova chromatin kupinda okutodza, uye ipapo dispiralized.

Izvi zvinobvumira kuwana polyploid neerekitironi apo DNA kugutsikana inowedzerwa. nyuchi kwakadaro nokuumba masero zvinowanikwa mwongo. Uyezve, pane nyaya, kana morekuru reDNA kaviri, uye nhamba okutodza inoramba zvakafanana. Vanozivikanwa se hwemapango hunotsimbirira purasitiki panzvimbo, uye vanogona kuwanikwa mumasero zvipembenene.

zvichireva mitosis

Mitotic weboka musimboti - inzira kuramba kuramba vanochengeta okutodza. Mwanasikana masero vane chete yakatarwa majini semubereki uye zvose zvainyanya hwokuzvarwa nahwo. Mitosis inodiwa:

- kukura zvipuka zvine masero akawanda zvipenyu (kubva Fusion kuti utachiona masero);

- misha repasi muchitokisi akaturikidzana ari pamusoro uye yokutsiva ropa masero (erythrocytes, leukocytes, maplatelet);

- kugadzira zvakakuvadza zvinyama (mune dzimwe mhuka tichikwanisa patsva chinhu chinodiwa vapone, akadai Starfish dzvinyu);

- asexual kubereka zvinomera uye dzimwe mhuka (invertebrates).

meiosis

unogovera utachiona masero nuclei mashandiro akasiyana zvishoma kubva somatic. Somugumisiro, vakawana masero kuti hafu majini ruzivo kupfuura zvavo vamutangira. Izvi zvinokosha kuti tirambe kuramba nhamba okutodza muchitokisi nerimwe muviri.

Meiosis kunoitika mumatanho maviri:

- rutapudzo siteji;

- equational Danho.

Zvakakodzera munguva muitiro zvinogoneka chete mumasero ane kunyange nhamba okutodza (diploid, tetraploid, uye geksaproidnym t. D.). Chokwadi, zvazvinosarira zvinobvira kupfuura meiosis uye masero vane shamisa yakatarwa okutodza, asi ipapo vana angasava chine musoro.

mashandiro Izvi zvinoita kusabereka mu interspecific michato. Sezvo ari utachiona mumasero vari nemhando dzakasiyana okutodza, izvozvo zvinoomesa Fusion dzavo uye chitarisiko musoro uye ivhu vana.

weboka rokutanga meiosis

danho anodzokorora zita vari mitosis: prophase, metaphase, anaphase, telophase. Asi pane zvimwe zvinokosha kusiyana.

1. Prophase: kaviri yakatarwa okutodza anoita dzakatevedzana transformations, achipfuura mumatanho mashanu (leptotena, zygotes, naPaquita, diplotene, diakinesis). Pane zvose nokuvonga uyu conjugation uye kuyambuka-pamusoro.

Conjugation - convergence ichi kubva homologous okutodza. In leptotene therebetween kuumba matete filaments uye ivai zygotene chromosome mbiri uye mugumisiro yaunganidzwa sechivako chromatids mana.

Crossover - muitiro muchinjikwa zvikamu Exchange pakati hanzvadzi chromatids kana homologous okutodza. Izvi zvinoitika panguva pachytene rwakazara. Kuvakwa panosangana (chiasm) okutodza. Muvanhu, exchanges izvi zvinogona kuva pakati matatu nemashanu kusvika makumi matanhatu. Mugumisiro izvi ndiko majini heterogeneity of kunoguma zvinhu, kana variability gametes.

Kana kunouya dariro diplotene pamusoro chromatids mana zvivako anoparadzwa uye hanzvadzi okutodza vzaimoottalkivayutsya. Diakinesis anopedza kuchinja kubva prophase kusvikira metaphase.

2. Metaphase: okutodza zvinozadzisa pedyo neequator muchitokisi.

3. Anaphase: okutodza, achiri rine chromatids maviri diverge kuti matanda sero.

4. Telophase: Vakagovana chokurukisa yaparadzwa, zvichiguma nokuumbwa maviri masero ane haploid vanochengeta okutodza vane kaviri uwandu DNA.

The meiotic kupesana wechipiri

Izvi anonziwo "mitosis, meiosis." Munguva iyoyo pakati maitikiro maviri DNA kuburitsa mufananidzo zvikasaitika, uye sero wechipiri anopinda prophase mumwechete yakatarwa okutodza, izvo akaramba pashure 1 telophase.

1. Prophase: okutodza dzora pemipata kuparadzana sero centre (vakasara aro akasiyana matanda muchitokisi), uye mumuhara collapses musimboti kuumbwa nokupesana chokurukisa dzinongoda perpendicular kune chokurukisa kuti weboka rokutanga.

2. Metaphase: okutodza chiri panzvimbo neequator, aumbwa metaphase ndiro.

3. Anaphase: okutodza akakamurwa chromatids kuti dzinozopenya kwose kwose.

4. Telophase: mumasero mwanasikana vakaumba chinoumba chromatids dispiralized kupinda chromatin.

Panoperera danho rechipiri mubereki sero, tine subsidiaries mana nehafu yakatarwa okutodza. Kana meiosis kunoitika pavanoparidza utachiona mutsetse (ndiko kuti, paumbwe dzepabonde masero), weboka vari nehasha gogonera, uye chakaumbwa nemakomo sero rimwe chete ine haploid yakatarwa okutodza uye zvitatu rutapudzo mhuru, kwete kutakura anodiwa mashoko magene. Ndivo zvakafanira kuti ave nechokwadi kuti zai dzisingaoneki vakasara chete nehafu majini zvinhu nomubereki muchitokisi. Uyezve, chimiro ichi weboka yenyukireya anopa chimiro mubatanidzwa mutsva majini, uyewo nhaka kwakachena alleles.

In nyore shanduro meiosis chiripo kana pane mumwe chete pakapuranga rokutanga Pasika, uye yechipiri pane Crossover. Masayendisiti zvinoratidza kuti chimiro ichi ndicho shanduka aizotangira pamusoro kwakajairika meiosis zvipuka zvine masero akawanda zvinenge. Zvichida pane dzimwe nzira fission zvenyukireya, izvo masayendisiti haasati kuziva.