Kev faib - yog dab tsi? Dab tsi yog cell division thiab naj npawb faib

Cov txheej txheem:

Kev faib - yog dab tsi? Dab tsi yog cell division thiab naj npawb faib
Kev faib - yog dab tsi? Dab tsi yog cell division thiab naj npawb faib
Anonim

Nyob hauv kab lus no peb yuav tau paub txog lub tswv yim ntawm kev faib. Qhov no yog ib lo lus uas muaj ntau yam uas tuaj yeem siv tau rau ntau thaj chaw ntawm tib neeg kev ua ub no, thiab nws cov txiaj ntsig tau pom nyob rau hauv qhov xwm txheej ntawm cov kab mob nyob. Txawm hais tias lub sijhawm thiab / lossis ib puag ncig ntawm cov txheej txheem, yog lub tswvyim tseem ceeb heev.

Cell faib

Cell division yog ib qho kev kawm tshwm sim nyob rau hauv uas, los ntawm kev faib ntawm ib lub cell, ob tug ntxhais qauv tsim, feem ntau zoo tib yam rau cov khoom ntawm leej niam system.

qhov tshwm sim ntawm kev faib yog
qhov tshwm sim ntawm kev faib yog

Prokaryotic faib suav nrog kev faib ua ob qhov sib npaug. Qhov no yog ua ntej los ntawm elongation ntawm lub xovtooj, tom qab tsim ntawm transverse septum, thiab tsuas yog tom qab ntawd qhov sib txawv.

Cov neeg sawv cev ntawm cov hlwb eukaryotic tuaj yeem faib ua ob txoj hauv kev: mitosis thiab meiosis. Txoj kev nthuav tawm yuav nyob ntawm hom cell.

Amitosis thiab kev npaj

Cell faib suav nrog cov txheej txheem ntawm amitosis thiab kev npaj.

Kev faib ncaj qha yog amitosis. Lawv hu nws ua ib hom kev faib ncaj qha. Qhov no tshwm sim rau lub interphase nucleus los ntawm constriction thiab tsis tsim ib tug ntxaiv los ntawm kev sib cais ntawm cellular lug thiab cov ntaub ntawv ntawm lub nucleus yuav tshwm sim. Amitosis yog qhov kev xaiv fission zoo tshaj plaws vim nws cov kev xav tau qis zog. Amitosis muaj ntau qhov zoo sib xws nrog kev tsim tawm ntawm tes ntawm prokaryotes.

Cov kab mob kab mob feem ntau suav nrog DNA molecule hauv daim ntawv ncig. Nws ib txwm nyob ib leeg thiab txuas nrog lub cell membrane. Ua ntej pib ntawm kev faib (kev tsim tawm), DNA pib rov ua dua thiab tsim 2 cov qauv molecular zoo tib yam. Tsis tas li ntawd, nyob rau hauv chav kawm ntawm kev faib, cov membrane ingrow ntawm cov 2 molecules. Raws li qhov tshwm sim, ntawm ob sab ntawm cov ntxaiv ntawm qhov sib txawv ntawm lub xov tooj ntawm tes muaj 2 ntu nrog cov ntaub ntawv keeb kwm uas zoo ib yam rau ib leeg. Daim ntawv no ntawm kev tsim tawm yog hu ua binary fission.

Kev faib yog txheej txheem ua ntej los ntawm kev npaj. Nws pib ntawm ib theem ntawm lub voj voog ntawm tes, hu ua interphase. Nyob rau theem no, cov txheej txheem tseem ceeb tshaj plaws tshwm sim, tso cai rau cov hlwb kom sib npaug. Protein biosynthesis yog nqa tawm, ob npaug ntawm cov qauv tseem ceeb tshaj plaws. Kuj tseem muaj ob npaug ntawm cov chromosome, uas muaj ob halves (chromatids). Lub sij hawm ntawm interphase nyob rau hauv cov kab mob ntawm cov tsiaj thiab cov nroj tsuag keeb kwm yuav siv sij hawm txog 10-20 teev. Mitosis raws li.

thaj av faib yog
thaj av faib yog

Mitosis and meiosis

Cell faib yog txoj hauv kev ntawm nws cov kev tsim tawm. Muaj ob txoj hauv kev tseem ceeb: mitosis thiabmeiosis.

Mitosis yog ib hom kev sib kis ntawm cov ntaub ntawv keeb kwm yav dhau los, thaum lub sij hawm uas ib daim qauv ntawm cov chromosomes qub tau khaws cia. Ib qho ntawm ob peb qhov zoo ntawm qhov kev faib tawm ntawm meiosis yog qhov tsis muaj teeb meem hauv lub xov tooj ntawm tes nrog ib qho ploidy index. Qhov no yog vim tsis muaj qhov yuav tsum tau siv ntawm chromosomal conjugation ntawm theem prophase. Cov txheej txheem no suav nrog cov theem ntawm prophase, metaphase, anaphase thiab telophase, ntawm qhov interphase tshwm sim. Tib cov kauj ruam tau pom hauv meiosis, tab sis lawv tshwm sim ob zaug nrog qee qhov sib txawv.

Meiosis yog kev faib tawm ntawm tes thaum lub sijhawm pom ib nrab ntawm tus lej chromosome. Qhov no zoo ib yam rau cov menyuam yaus. Thawj tus piav txog nws hauv cov tsiaj yog W. Flemming hauv 1882, thiab cog meiosis tau piav qhia los ntawm E. Strasburger hauv 1888.

Meiosis yog qhov tsim ntawm gametes. Nyob rau hauv lub chav kawm ntawm kev txo qis, ob qho tib si spores thiab kab mob cell qauv nrog ib chromosome teem tau ib chromosome los ntawm txhua chromosome, tsim los ntawm ob chromatids thiab muaj nyob rau hauv ib tug diploid cell. Ntxiv fertilization yuav tso cai rau cov kab mob tshiab kom tau txais cov chromosome teem rau hauv daim ntawv diploid. Lub karyotype tseem tsis hloov pauv.

Administrative-territorial form of territorial division

Territorial division yog ib qho kev faib ntawm thaj chaw uas muab los ntawm kev tswj hwm-ib cheeb tsam ntawm lub xeev. Feem ntau qhov no siv rau lub zog unitary. Raws li lawv txoj kev faib rau hauv ib cheeb tsam thiab ntu, ib qho khoom nruab nrog cev raug tsim los ua lub luag haujlwm rau ib thaj chaw tshwj xeeb. Kev sib cais tuaj yeem tshwm sim los ntawm ntuj, kev nom kev tswv, haiv neeg thiab kev lag luam. Daim ntawv tswj hwm-ib thaj tsam ntawm kev faib tawm kuj tseem siv hauv tsoomfwv cov xeev. Txawm li cas los xij, tsis zoo li cov qauv kev sib koom ua ke, ib lub koom haum muaj cov cuab yeej sib raug zoo (tsoom fwv teb chaws).

kev faib yog ib yam khoom
kev faib yog ib yam khoom

About ATD

Cov ntsiab lus ntawm tsoomfwv feem ntau tau muab cov qauv kev sib koom ua ke ntawm kev tswj hwm-ib thaj tsam ntawm cov cai ntawm kev sib cais. Cov chav kawm uas yog cov ntsiab lus ntawm lub koomhaum feem ntau yog hais txog cov ncauj lus ntawm kev tswj hwm tus kheej hauv zos thiab kev tswj hwm. Cov npe ntawm lawv cov cai raug txiav txim siab thiab tiv thaiv los ntawm cov cai tshwj xeeb.

Kev faib thaj chaw yog ib qho kev txwv uas tej zaum yuav tshwm sim los ntawm kev tawg ntawm ib lub xeev uas muaj cov kev faib zoo sib xws. Yav dhau los kev tswj hwm ciam teb sab hauv tuaj yeem dhau los ua qhov kev txwv tshiab ntawm thaj chaw ntawm lub tebchaws tsim tshiab. Txawm li cas los xij, feem ntau qhov no dhau los ua qhov teeb meem, uas ua rau muaj kev tsis sib haum xeeb hauv xeev.

direct division yog
direct division yog

Kev faib ua lej

Hauv kev ua lej, kev faib yog ib qho haujlwm tshwj xeeb uas yog qhov hloov pauv ntawm kev sib npaug. Hauv kev ua lej, nws txhais tau hais tias yog siv cov nyuv, hlais lossis obelus, nrog rau kab rov tav.

Qhov kev txiav txim no zoo ib yam li kev sib npaug, qhov twg muaj kev hloov pauv rau kev rov ua dua ntawm qhov sib ntxiv ntawm tus lej. Txawm li cas los xij, qhov tshwm sim ntawm kev faib tawm yog qhov kev txiav txim rov qab, suav nrog kev rho tawm dua.

Cia peb paub txog kev faib ua piv txwv: 15/4=?

Cov lus qhia txhais cov lus nug txog pes tsawg zaus tus lej 4 rov qab thaum rho tawm ntawm 15.

Rov ua dua qhov rho tawm ntawm 4 yuav qhia peb cov ntsiab lus ntawm peb 4s thiab ib qho 3. Hauv qhov no, 15 yog qhov sib faib, 4 yog qhov sib faib, triple repetition ntawm 4 yog qhov tsis tiav quotient, thiab 3 yog qhov seem. Qhov kawg tshwm sim ntawm kev sib faib ua haujlwm tseem hu ua qhov piv.

qhov sib txawv yog faib
qhov sib txawv yog faib

Qhia cov lej

Tsis txhob hnov qab tias kev faib thiab cov khoom yog cov ntsiab lus sib txawv. Cov tom kawg yog hais txog kev sib npaug. Zoo siab uas tau hais los ntawm no thaum tib neeg feem ntau nug cov lus nug zoo li no.

Tam sim no, kev faib yog siv, muaj feem xyuam rau ntau tus lej tsim thiab muab faib los ntawm tus txiv neej. Niaj hnub no muaj kev faib: natural, rational, complex thiab integers, thiab qhov no kuj muaj xws li kev faib ntawm polynomials, los ntawm xoom thiab algebraic.

"Qhov txawv yog faib." Ib nqe lus zoo sib xws kuj muaj feem ntau pom hauv Internet, tab sis qhov no tsis muaj tseeb. Qhov txawv yog tus naj npawb (r), qhia tag nrho cov chav nyob uas tau tsim thaum ib feem ntawm kev suav raug rho tawm los ntawm lwm tus: a - b \u003d c, qhov twg a yog tus rho tawm, b yog qhov subtrahend, thiab c yog qhov txawv. Cov ntsiab lus no sib npaug thiab tib yam rau txhua daim ntawv ntawm cov lej, xws li cov zauv feem lossis cov lej, thiab lwm yam. Tsis txhob ua zoo li blondes nug cov lus nug "yog qhov sib txawv ntawm qhov sib npaug lossis faib?". Qhov txawv yog qhov sib txawv ntawm qhov sib npaug.

Dib by zero

cell division yog
cell division yog

Nyob rau hauv cov txheej txheem lej lej teev, faib los ntawm xoom tseem tsis tau txhais.

Thaum nws los txog rau kev faib ua haujlwm me me lossis ua ntu zus uas tsis yog xoom, nws tuaj yeem sib cav tias cov ntsiab lus nrog qhov sib faib ua haujlwm hauv daim ntawv xoom muaj qhov ua haujlwm tsis tiav. Yog hais tias koj faib ib tug muaj nuj nqi uas yog bounded thiab deb ntawm xoom los ntawm ib tug infinitely ib tug me me, ces koj yuav tau txais ib tug infinitely loj. Uncertainty yog qhov piv ntawm 2 infinitesimal functions (0/0). Nws tuaj yeem hloov pauv kom ua tiav qee qhov txiaj ntsig.

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