Yuav ua li cas yog polyploidy? Yuav ua li cas lub luag hauj lwm yog nws ua si nyob rau hauv lub xaiv thiab nyob rau hauv cov xwm

Tom qab nyeem ntawv no tsab xov xwm, koj yuav kawm tau dab tsi polyploidy. Peb yuav saib lub luag hauj lwm nws plays. Koj kuj yuav kawm txog yog lub hom polyploidy.

Kev Kawm Ntawv polyploids

Ua ntej ntawm tag nrho cov, qhia rau peb hais txog dab tsi yog meant ntawm no mysterious lo lus. Hlwb los yog cov neeg uas muaj ntau tshaj ob poob lawm ntawm chromosomes yog hu ua polyploids. Polyploid hlwb nrog tsawg zaus yog lub txiaj ntsim ntawm "yuam kev" mitosis. Qhov no tshwm sim thaum lub chromosomes raug muab faib, thiab cytokinesis tshwm sim. Yog li hlwb tej zaum yuav tsim nyob rau ntawm ob tus naj npawb ntawm cov chromosomes (diploids). Yog hais tias lawv yog dhau los ntawm lub interphase, yuav qhia, nws yuav muab sawv mus rau (kev sib deev los yog asexually) tshiab cov neeg uas nws lub hlwb yuav muaj ob zaug ua ntau chromosomes tshaj lawv niam lawv txiv. Raws li, qhov txheej txheem ntawm tsim - uas yog polyploidy. Polyploid nroj tsuag muaj peev xwm yuav tsim artificially siv colchicine - alkaloid suppressing lub tsim ntawm lub mitotic ntxaiv los ntawm ib tug ua txhaum cai ntawm microtubule tsim.

zog polyploids

Cov nroj tsuag volatility yog feem ntau npaum li cas nqaim tshaj li hais tias ntawm lub hais txog diploid, vim hais tias txhua noob yog sawv cev los ntawm lawv tsawg kawg yog ob zaug tus xov tooj. Thaum cleavage ntawm lub progeny homozygous rau ib co recessive noob neeg roos xwb 1/16 es tsis txhob ntawm 1/4 nyob rau hauv diploids. (Nyob rau hauv ob qho tib si zaum nws yog assumed tias lub zaus ntawm recessive alleles yog 0.50.) Polyploidy peculiar selfing, ntxiv txo lawv cov volatility, txawm lub fact tias lawv muaj feem diploids advantageously ntoo khaub lig pollinated.

Qhov twg muaj polyploids

Yog li ntawd, peb tau teb rau lo lus nug, yog dab tsi polyploidy. Tab sis qhov twg muaj xws li nroj tsuag?

Ib txhia polyploids yog zoo yoog mus rau qhuav qhov chaw los yog tsawg kub tshaj tus thawj diploid daim ntawv no, thaum lwm tus neeg yog zoo dua suited kom meej av hom. Vim li no, lawv yuav txiav txim nyob rau hauv qhov chaw nrog huab tej yam kev mob ntawm lub neej, nyob rau hauv uas lawv diploid pog koob yawg koob tej zaum yuav tau tuag. Nrog ib tug me me zaus lawv tshwm sim nyob rau hauv ntau natural coob. Lawv yog cov sib zog tshaj lub sib nug xov diploids, tuaj nyob rau hauv outbreeding. Nyob rau hauv cov ntaub ntawv no, sai li sai raws li tej zaum yuav ua fertile hybrids. Tsawg polyploids hybrid keeb kwm tsim los ntawm doubling tus xov tooj ntawm chromosomes nyob rau hauv ib tug diploid muaj menyuam tsis taus hybrids. Qhov no yog ib txoj kev uas plodovistosti rov qab.

Tus thawj sau ua ntaub ntawv cov ntaub ntawv ntawm polyploidy

Nws yog yog li ntawd, tsis tshua muaj heev, los ntawm polyploid hybrids tsim ntawm radishes thiab qhwv. Qhov no yog thawj zoo documented cov ntaub ntawv ntawm polyploidy. Ob genera mus rau lub tsev neeg ntawm crucifers thiab zoo txog. Nyob rau hauv Somatic hlwb , thiab ob hom chromosomes yog 18, thiab cov thawj meiotic metaphase 9 yeej ib txwm kuaj officers ntawm chromosomes. Muaj ib co teeb meem, nws twb tau los ntawm ib tug hybrid ntawm cov nroj tsuag. Nyob rau hauv meiosis, nws muaj 18 unpaired chromosomes (9 thiab 9 los ntawm qos liab los ntawm zaub qhwv) thiab yog kiag li muaj menyuam tsis taus. Cov no hybrid nroj tsuag polyploidy nthawv tsim, uas nyob rau hauv Somatic hlwb yog 36 chromosomes thaum lub sij hawm meiosis thiab tsis tu ncua tsim 18 officers. Nyob rau hauv lwm yam lus, polyploid hybrid muaj tag nrho cov 18 chromosomes raws li ib tug qos liab, thiab zaub qhwv thiab lawv functioned nquag. Qhov no hybrid yog heev muaj menyuam coob coob.

Polyploids-nroj

Ib txhia polyploids tshwm sim zoo li cov nroj nyob rau hauv ib daim teb uas muaj feem rau tib neeg kev ua ub no, thiab tej zaum lawv muaj tiav zoo kawg li txoj kev vam meej. Ib tug zoo-paub piv txwv - tus inhabitants ntawm lub ntsev marshes ntawm cov genus Spartina. Ib hom, S. maritima (pictured hauv qab no), yog pom nyob rau hauv lub swamps raws coasts ntawm cov teb chaws Europe thiab Africa. Lwm yam, S. alterniflora, qhia mus rau lub UK nyob rau hauv lub sab hnub tuaj ntawm North America nyob ib ncig ntawm 1800 thiab tom qab kis tau lug, txoj kev loj hauv zos colony.

nplej

Ib tug ntawm cov tseem ceeb tshaj plaws polyploid cog pawg yuav suav hais tias ib yam ntawm cov nplej Triticum (pictured hauv qab no). Feem ntau nyob rau hauv lub ntiaj teb no grain cov qoob loo - mos nplej (T. aestivum) - muaj 2n = 42. Mos nplej originated tsawg kawg yog 8,000 xyoo dhau los, tej zaum nyob rau hauv Central teb chaws Europe, raws li ib tug tshwm sim ntawm tej yam ntuj tso hybridization ntawm cultivated nplej, uas tau 2n = 28, muaj ib tug tsiaj qus cereal tib hom uas muaj 2n = 14. Tsiaj qus nyom, tej zaum loj hlob zoo li nroj ntawm cov nplej. Hybridization, muab sawv mus mos nplej, yuav tshwm sim ntawm polyploidy nkaus li los ntawm lub sij hawm rau lub sij hawm nyob rau hauv lub coob txog ob niam txiv hom.

Nws yog yuav hais tias sai li sai tau raws li lub 42-chromosome nplej nrog nws pab tau tej yam tshwm sim sawv nyob rau hauv lub margins ntawm cov thawj cov tswv teb, lawv tam sim ntawd pom nws thiab xaiv rau ntxiv sau qoob. Ib tug ntawm nws niam txiv cov ntaub ntawv, 28-chromosome nplej yog cultivated, nws yog lub txiaj ntsim ntawm tus hybridization ntawm ob qus hom chromosome 14 los ntawm lub Middle East. Hom nplej, nrog 2n = 28, thiab tam sim no tseem yuav cultivated nrog 42-chromosome. Tej nplej chromosome 28 yog qhov tseem ceeb ntawm grain rau zus tau tej cov nplej zom vim lub high adhesiveness ntawm cov protein. Ntawm no lub luag hauj lwm ua si los ntawm polyploidy.

Triticosecale

Tsis ntev los no kev tshawb fawb tau qhia tias cov tshiab cov kab tau los ntawm hybridization yuav ua tau kom ua liaj ua teb ntau lawm. Polyploidy rau tsob nroj qe yog siv heev lug. Tshwj xeeb tshaj yog pheej yog Triticosecale - pab pawg neeg manmade hybrid ntawm hom qoob mog (Triticum) thiab rye (Secale). Ib txhia ntawm lawv, sib txuas tawm los ntawm nplej rye ruggedness, feem ntau ruaj khov linear xeb - kab mob, ua rau zoo kawg kev puas tsuaj rau ua liaj ua teb. Cov zog yog tshwj xeeb yog ib qho tseem ceeb nyob rau hauv high-altitude cov cheeb tsam ntawm lub tropics thiab subtropics, qhov twg xeb - lub ntsiab zoo tshaj limiting cov sau qoob mog. Triticosecale yog tam sim no zus rau ib tug loj scale thiab yog heev nrov nyob rau hauv Fabkis thiab lwm lub teb chaws. Lub nto moo tshaj plaws yog ib tug 42-chromosome kab ntawm no cereal. Nws twb tau los ntawm doubling tus xov tooj ntawm chromosomes tom qab hybridization ntawm chromosome 28 Nplej 14-chromosomal rye.

Qhov ntau haiv polyploids

Nyob rau hauv cov xwm, lawv yog npaum li cas nyob rau hauv tus ntawm lwm yam kev mob, tsis vim hais tias ntawm tib neeg kev ua ub no. Lawv zoo li - ib yam ntawm cov tseem ceeb tshaj plaws evolutionary mechanisms. Niaj hnub no muaj ntau yam polyploid sawv cev nyob rau hauv lub ntiaj teb no muaj (ntau tshaj ib nrab ntawm tag nrho cov nroj tsuag tsiaj). Ntawm lawv yog cov muaj ntau lub tseem ceeb tshaj plaws qoob loo - tsis tsuas nplej, tab sis kuj paj rwb, qab zib pas nrig, txiv tsawb, qos yaj ywm thiab sunflower. Yuav kom qhov no daim ntawv teev yuav muab ntxiv zoo nkauj tshaj plaws vaj paj - Chrysanthemums, pansies, dahlias.

Tam sim no uas koj paub tias dab tsi polyploidy. Nws lub luag hauj lwm nyob rau hauv ua liaj ua teb, raws li koj tau pom, yog heev.