Video: Lactose operon ua haujlwm li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Cov lac , los yog lactose , ua haujlwm muaj nyob rau hauv E. coli thiab lwm yam kab mob enteric. Qhov no ua haujlwm muaj gene coding rau cov proteins nyob rau hauv tus nqi thauj lactose mus rau cytosol thiab zom nws mus rau hauv qabzib. Cov piam thaj no tom qab ntawd siv los ua kom muaj zog.
Tsis tas li ntawd, lactose tig rau lub lac operon li cas?
Cov lac operon ua ntawm E. coli muaj cov gene koom nrog lactose metabolism. Nws yog qhia tsuas yog thaum lactose tam sim no thiab qabzib tsis muaj. Ob tug regulators tig tus ua haujlwm "on" thiab "off" nyob rau hauv teb rau lactose thiab qib qabzib: cov lac repressor thiab catabolite activator protein (CAP).
Tsis tas li ntawd, dab tsi tshwm sim rau lac operon thaum muaj cov piam thaj thiab lactose? Thaum ob leeg muaj cov piam thaj thiab lactose , cov noob rau lactose metabolism yog transcribed mus rau ib qho me me. Maximal transcription ntawm lub lac operon tshwm sim tsuas yog thaum qabzib yog tsis tuaj thiab lactose yog tam sim no . Qhov kev txiav txim ntawm cyclic AMP thiab catabolite activator protein tsim cov nyhuv no.
Kuj nug, yuav ua li cas yog tias qib lactose qis?
Yog tus qib ntawm inducer lactose yog qis ces tus neeg teb xov tooj yog rov thaiv los ntawm repressor kom cov txheej txheem genes repressed ib zaug dua; txhawm rau txhawm rau tsim cov enzymes.
Yuav ua li cas yog ib qho operon koom?
Prokaryotic structural genes ntawm cov haujlwm muaj feem xyuam feem ntau koom rau hauv cov neeg ua haujlwm , txhua yam tswj los ntawm kev sau los ntawm ib tus neeg txhawb nqa. Kev tswj hwm cheeb tsam ntawm ib ua haujlwm suav nrog tus neeg txhawb nqa nws tus kheej thiab thaj av ib puag ncig tus txhawb nqa uas cuam tshuam txog kev hloov pauv tuaj yeem cuam tshuam rau kev hloov pauv.
Pom zoo:
Cov haujlwm ua haujlwm li cas hauv lej?
Hauv kev ua lej, kev ua haujlwm yog qhov kev sib raug zoo ntawm cov teeb tsa uas koom nrog txhua lub ntsiab lus ntawm thawj zaug raws nraim ib qho ntawm cov txheej thib ob. Cov piv txwv zoo yog cov haujlwm los ntawm cov lej mus rau cov lej lossis los ntawm cov lej tiag mus rau cov lej tiag. Piv txwv li, txoj haujlwm ntawm lub ntiaj teb yog lub luag haujlwm ntawm lub sijhawm
Yuav ua li cas lac operon ua haujlwm quizlet?
Yog tias muaj lactose tam sim no, nws khi rau thiab inactivates lub repressor los ntawm ua rau nws poob tawm ntawm tus neeg teb xov tooj. Lub operon yog induced thaum lactose molecules khi rau cov protein repressor. Yog li ntawd, cov protein repressor poob nws cov duab thiab ntog tawm ntawm tus neeg teb xov tooj cheeb tsam
Yuav ua li cas rau E coli thaum muaj lactose?
Yuav ua li cas rau E. coli thaum tsis muaj lactose? Cov noob uas tsim cov enzymes xav tau los rhuav tshem lactose tsis qhia. Lub repressor protein thaiv cov noob los ntawm kev ua mRNA
Yog vim li cas trp operon suav hais tias yog ib tug repressible operon?
Lub tryptophan (trp) operon system yog ib hom repressible operon system. Thaum tryptophan tam sim no, nws khi lub trp repressor thiab induces ib tug conformational hloov nyob rau hauv cov protein, ua rau nws khi tus neeg teb xov tooj trp thiab tiv thaiv transcription (operon yog repressed)
Cov txheej txheem dab tsi yog lub luag haujlwm rau txoj haujlwm ua haujlwm sib txawv?
Position-effect variegation (PEV) tshwm sim thaum cov noob ib txwm nyob hauv euchromatin yog sib xyaw nrog heterochromatin los ntawm kev hloov kho lossis hloov pauv. Thaum lub ntim ntim heterochromatin kis thoob plaws heterochromatin / euchromatin ciam teb, nws ua rau kev hloov pauv ntawm kev ntsiag to hauv tus qauv stochastic