Sezvo kuwedzera masero. Kuwedzera uye kuwanda masero

Zvichida hapana kakawanda akadzidza pachikoro zvipenyu pfungwa chepurogiramu pane sero. Sezvo paine nezvevanakomana 5 pamusoro dzinongoitika nhoroondo mukirasi, uye ipapo kurapwa 6 replicates sezvo mhando uye sero kupesana nzira yayo. Muna 7th uye rechi8 mamakisi akadzidza kubva pfungwa nemaonero chirimwa, mhuka uye mavambo kwevanhu. Grade 9 zvinosanganisira hanya yomunyika pezvakaitwa kuitika mairi, icho samolecular mamiriro. At 10 uye 11 ndiyo sero pfungwa, zvakawanikwa uye shanduka.

Chirongwa inovakwa kuti nzira nokuti izvi duku zvivako, "Nzira Dzinovaka upenyu," zvinokosha zvinhu chero muviri. All anokosha, pezvakaitwa, kukura, paumbwe - zvose chokuita noupenyu, kunze navo uye mavari. Saka, munyaya ino tichakurukura huru wokuberekana, sero kukura uye nhoroondo yawanika.

okutanga masero

Izvi STRUCTURAL nezvimedu zvidiki chaizvo kukura. Naizvozvo, nokuti yawanika zvakatora nguva refu uye kusikwa kuchiitirwa rwokugadzira. Nokuti kokutanga cellular maumbirwo mhenyu chirimwa rinenge achiona Robert guk. Maiva muna 1665. In kuitira kuti funga, iye akazogadzira maikorosikopu wokutanga. mudziyo uyu unenge usisina kutombofanana ano rinokudza mano. Asi, zvakanga zvakafanana mashomanana akaronga pakati loop, achipa kuwedzera.

Achishandisa mudziyo ichi, musayendisiti vaiona chikamu koko muti. Zvaakaona aiva mavambo kukura vanoverengeka sayenzi kufanana uye zvipenyu zvavo. A muzvizhinji kuti zvakasimba abutting masero anenge akaenzana pakukura chimiro. Hooke akavadana cella, izvo zvinoreva "muchitokisi".

Naizvozvo akaita zvinoverengeka zvakawanwa kuti akabvumira ruzivo kukura, kuunganidza uye kuguma sayenzi dzinoverengeka anobatanidzwa pakudzidza.

1. 1675 - musayendisiti Malpighi akadzidza akasiyana siyana muchitokisi chimiro uye vakasvika pakugumisa kuti zvinokonzerwa kumativi kana denderedzwa matema akazara upenyu muto.
2. 1682 - N. Grew Malpighi akasimbisa zvakawanikwa, uye akadzidzawo nemamiriro muchitokisi membrane.
3. 1674 - Antoni Van Leeuwenhoek anovhura masero mabhakitiriya, uyewo ropa uye dzisingaoneki marongerwo.
4. 1802-1809 gg. -. Sh-Brissot uye Mirbeau Zh B. Lamark anoratidza kuvapo zvakafanana pakati nyama uye mhuka uye chirimwa masero.
5. 1825 - chinozarura Purkinje sero musimboti shiri pabonde.
6. 1831-1833 gg. - Robert Brown anoratidza pamberi musimboti iri chirimwa masero uye anotanga pfungwa kukosha wechipfuwo akafanana, panzvimbo muchitokisi Kamudzira, sepakutanga akafunga.
7. 1839 - Theodor Schwann anogumisa kuti zvose zvipenyu akaumbwa masero, uyewo zvakafanana. yakapfuura mumwe (ramangwana sero dzidziso).
8. Of 1874-1875. - Chistyakov uye Strasburger rakavhurika sero chokuwanziridza nzira - mitosis, meiosis.

All zvimwe Zvakawanikwa mumunda foni zvivako, avo mashandiro, uye basa kusiyana muupenyu zvipenyu rwaiitwa nokuda ndichibvunza kukura rinokudza uye chiedza midziyo inokosha nokukurumidza.

sero nokupesana

Sero rimwe nerimwe riri hwose anoita foni kutenderera - nguva hwake kubva pakuzvarwa kusvikira pakufa (kana kupesana). Uyezve, hazvina basa, zviri mhuka kana miriwo. The upenyu kutenderera ndiro vose zvavo, uye kazhinji, pakupera masero ayo zvirege kupfurikidza kukamuka.

Zvechokwadi, kwete zvinenge zvose, izvi ndizvo zvakafanana. For eukaryotic uye prokaryotic zviri unopfuura zvakasiyana, pane kusiyana Mashoko chirimwa uye mhuka masero.

Sezvo kuwedzera masero? Pane zvakawanda zvinokosha nzira.

1. Mitosis.
2. Meiosis.
3. Amitosis.

Mumwe nomumwe wavo inomirira dzinoverengeka pezvakaitwa maitikiro. Uye vose azvaiitwa dzakananga kuti zvipuka zvine masero akawanda Utachiona, zvose chirimwa uye mhuka mavambo. In unicellular kubereka kunoitika nokungonyepedzera vachigoverana nepakati. Kureva, sero kubereka nzira havasi zvakafanana. Pane kunyange zvakadaro chinhu sezvo muchitokisi kuzviuraya. Izvi kwataisvika masero pane kupatsanura kwendangariro.

Sezvo kuwedzera masero, zvakadai nemabhakitiriya, zvitema-mutema algae, vamwe nyore? Asexually, nyore nzira: zviri masero kaviri muna muchitokisi pamadziro inoumbwa transverse kana longitudinal kukweva uye mumwe Sero rakakamurwa maviri hutsva, akafanana rwaamai muviri.

Izvi anonzi zvakananga muchitokisi nokupesana. Vawande, uye unicellular utachiona, asi haana chokuita mitotic kana meiotic pezvakaitwa kuti. Zvaitika chete mumuviri zvipuka zvine masero akawanda zvipenyu.

mitosis

In zvipuka zvine masero akawanda venyama rine mabhiriyoni masero. Uye mumwe nomumwe wavo anoedza kupedza kwayo upenyu inaye, zviri kusiya mwana, uye kwete kufa. Masero bereka nokuda kuparadzanise, asi izvi hazvisi zvose zvavo zvakafanana.

Somatic mamiriro (kureva masero zvakadaro zvose kunze utachiona) nzira yavo vakasarudzwa kuti kubereka kana amitosis mitosis. Zvinofadza chaizvo, capacious uye kunzwisisa chichiitwa, izvo zvakazoita kubva mubereki diploid masero (i.e., miviri vanochengeta okutodza) maviri akafanana wake mwanasikana pamwe chete diploid sezvamunoita.

The yose muitiro ine pfungwa huru mbiri:

1. Mitosis - fission renyukireya wayo yose zviri.
2. Cytokinesis - mukuru weboka protoplasm (cytoplasm uye zvose cellular organelles).

azvaiitwa kuitika panguva imwe chete, zvichiita kuti paumbwe mukuru-mugiredhi mubereki makopi aiitwa maduku.

Mitosis ine zvikamu zvina (prophase, metaphase, anaphase, telophase) uye sezvayakanga asati weboka - interphase. Funga zvose.

interphase

Kuwedzera uye kuwanda masero rinoitwa panyika upenyu muviri. Zvisinei, kwete masero ose vane nguva chete kuvapo. Vamwe vavo vanofa mumazuva maviri kana matatu (masero ropa), vamwe vanoramba operative hwose (huta).

Asi akawanda oupenyu sero rimwe inochengeterwa mamiriro inonzi interphase. Iyi ndiyo nguva wokugadzirira weboka masero vakaumba akura, izvo rinotangira 90% nguva yose muitiro.

The zvipenyu kukosha danho iri kuunganidza zvokudya, RNA uye mapuroteni kwetunhu DNA mamorekuru. Pashure pezvose, pashure kupatsanura kupinda mumwe mwanasikana muchitokisi anofanira kuwana chaicho uwandu organelles, zvinhu uye kuvabereki zvinhu, zvakadini waiva mai. Kuti izvi zviitike munhu doubling aripo zvivako, kusanganisira DNA tambo.

Kazhinji, kuti interphase kunoitika mumatanho matatu:

• presynthetic;
• chakaita zvokugadzirwa;
• postsynthetic.

Result: kuunganidza zvokudya, simba uye DNA molecules mamwe kupatsanura pezvakaitwa. Saka, danho ichi - ndiko chete kutanga sei sero Anowanza mberi.

prophase

Panguva iyi, zvinotevera pezvakaitwa makuru ndiwo:

• wokuparadza Kamudzira yenyukireya;
• Zvibvisike (vari ichiputswa) nucleoli;
• okutodza zvava kuonekwa pasi maikorosikopu nokuda Achitsaudzira (akamonyoroka) yechivako chacho;
• centriole yokubudisa muchitokisi matanda, kudhonza chokurukisa nokuita fission.

Panguva iyi mhuka sero kubereka hapana akasiyana nevamwe vose.

metaphase

danho Izvi hupfupi, chete anenge 10 maminitsi. Its hwaro ndechokuti chromatids zvakarongwa pamusoro muchitokisi neequator. Akaya chokurukisa mumwe mugumo namatirai centriole panguva muchitokisi mapango, uye dzimwe centromere nerimwe chromatids. Pakati masero ari anenge asina chokuita uye saka nyore vakagadzirira disconnection.

anaphase

Pfupi pavaipfuura rose mitotic yatinofema. Ya anenge 3 maminitsi. Munguva iyi, mumwe chromatid anoenda padanda masero ake uye rinopedzisa chisipo hafu amene, akatendeuka kupinda dzose nemamiriro chromosome.

Zvisinei, dzidzo ichi zvinoda rinokosha enzayemu - telomerase. Wakapfuurira kuwanda yaro interphase.

telophase

Mumwe Sero danda rinowanika genetic zvinhu zvayo, izvo zvinopfekwa ari Kamudzira yenyukireya, achiumba musimboti. Nucleoli kuoneka. Yose muitiro zvinotora maminitsi anenge 30. Ndizvo chaizvo kwenguva refu. Izvi imhaka paumbwe nucleolar uye renyukireya Kamudzira kunoda mukuru simba mari uye Kuwanikwa chivakwa zvinhu - zvinokurisa (mapuroteni, makabhohaidhiretsi, makemikari, mafuta, amino acids).

cytokinesis

Izvi rinopedzisa rose mitotic yatinofema. Protoplasm inokamukana pamwe organelles zvakasimba muna hafu, uye mumwe mwanasikana nomumwe anogamuchira zvakangofanana sezvo mukoma wake. Zvadaro mhiri masero vakaumba kukweva mapuroteni (actin hunhu) iro anorumanya chivako mhiri uye runoparadzanisa kuva vaviri vakaenzana, asi vashoma kukura zvichienzaniswa mubereki masero.

Panguva iyi, pane dzimwe kusiyana masero nezvipfuwo rurege inoparadzirwa chirimwa sero. Chokwadi kuti puroteni iri chirimwa zvivako zvishoma uye actin havapo. Naizvozvo, hapana constriction achiumbwa pakati, uye panoparadzana rusvingo, kumativi zvose izvo pulp iri rakachengetedzwa. Izvi zvinopa chirimwa sero Rigidity, pamatanda unoumba foni rusvingo.

Kuwedzera uye chokuwanziridza masero munzira achiteverwa zvatinosiita upenyu kutenderera: specialization, paumbwe nhengo dzomuviri, rinoita basa uye kupesana, kana rufu.

Camadas masero vavo kubereka

Musi mubvunzo sei foni reproduces, mhinduro inogona kupiwa kwokunatsiridzwa chii. Pashure pezvose, zvatakurukura ari dzinotsanagura mitosis hunhu chete somatic hurongwa. Nepo utachiona masero bereka mune neimwewo nzira, kana pane, meiosis.

Izvi ndiyo hwaro vakadaro anokosha kwemhuka sezvo gametogenesis, kureva kurara kubereka. Kukura utachiona masero kunoitika mumatanho dzakawanda. Naizvozvo, meiosis - kunyanya kunzwisisa uye capacious kupesana pane mitosis.

Nokuti chirimwa Sero meiosis - sporogenesis hwaro, ndiko kuti, paumbwe bonde masero. The chikuru zvoutachiona kunoita meiosis nokuti zvinenge zvose ndechokuti somugumisiro anoumba zvina haploid (pamwe nehafu kana chimwe vanochengeta okutodza) utachiona masero. Sei? To panosangana (Fusion vechirume gametes) chakaitika diploid zygote kupora mune (mudumbu ramangwana) itsva. Izvi zvinopa majini vakasiyana zvipenyu, zvichitungamirira Gene anofambidzana, pakuonekwa uye nenzvimbo itsva zvinhu.

Sechivako nedanho meiosis

Pane huru mapoka maviri meiosis: Kuderedza uye equational. Mumwe nomumwe zvinosanganisira zvose zvakafanana danho souya mitosis: prophase, metaphase, anaphase uye telophase. Chimbofunga zvishoma nomumwe wavo.

rutapudzo nokupesana

Chinonyanya kukosha: rimwe masero diploid vanoumba maviri haploid, pamwe nehafu yakatarwa okutodza. maitikiro:

• prophase I;
• metaphase I;
• anaphase I;
• telophase I.

On nechimwe maitikiro inodzokororwa zvose zvakafanana kutendeuka sezvo kuti nhengo matanho mitosis. Zvisinei, mumwe musiyano uchiripo: mu interphase hapana doubling DNA, zviri chete chakakamurwa nepakati, uye zvose. Naizvozvo, chete hafu majini mashoko inowira mumwe mwanasikana muchitokisi. Izvi kupararira kutanga masero mhuka uye chirimwa chokuita zvepabonde.

equational nokupesana

The meiotic nekupesana wechipiri, zvichiguma nokuumbwa kunyange vaviri masero nomumwe yapfuura mumwe. Zvino pane ina fanana haploid ishamwari rinova dzezvepabonde mhuka kana chirimwa masero. Step equational kutozopesanisa prophase II, metaphase II, anaphase II, telophase II.

Saka, mubvunzo sei foni replicates, ane mhinduro nani yakaoma uye capacious. Pashure azvaiitwa, sezvo mamwe zvose zvichiitika zvipenyu, zviri dzakatetepa chaizvo uye anoumbwa imwe muzvizhinji kuti nzendo.