Cov proteins ua haujlwm li cas los ua kom cov membranes xaiv permeable?
Cov proteins ua haujlwm li cas los ua kom cov membranes xaiv permeable?

Video: Cov proteins ua haujlwm li cas los ua kom cov membranes xaiv permeable?

Video: Cov proteins ua haujlwm li cas los ua kom cov membranes xaiv permeable?
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Cov lus teb yog cov proteins . Cov protein dot saum npoo ntawm bilayer, ntab zoo li rafts. Ib txhia ntawm no proteins muaj cov kab, lossis qhov rooj nruab nrab ntawm lub xov tooj ntawm tes thiab ib puag ncig. Cov channel cia cov khoom loj uas yog hydrophilic thiab feem ntau tsis tuaj yeem dhau los ntawm daim nyias nyias mus rau hauv lub cell.

Raws li txoj cai, kev thauj cov protein ua li cas thiaj li ua rau lub membrane xaiv permeability?

Ib plasma daim nyias nyias yog permeable rau tej molecules uas ib tug cell xav tau. thauj cov protein hauv cell daim nyias nyias pub rau xaiv kev hla ntawm cov molecules tshwj xeeb los ntawm ib puag ncig sab nraud. Txhua thauj protein yog tshwj xeeb rau ib qho certian molecule (qhia los ntawm cov xim sib xws).

Ib tug kuj yuav nug, dab tsi yog lub luag haujlwm ntawm lub hlwb xaiv permeable plasma membrane? Ib qho kev xaiv permeable cell membrane yog ib qho uas tso cai rau qee cov molecules lossis ions kom dhau los ntawm nws los ntawm kev ua haujlwm lossis tsis ua haujlwm. thauj . Active thauj cov txheej txheem xav kom lub cell siv lub zog txav cov ntaub ntawv, thaum passive thauj tuaj yeem ua tsis tau siv lub zog ntawm tes.

Ib tug kuj yuav nug, vim li cas cov membranes impermeable rau feem ntau cov tshuaj?

Lawv yog impermeable vim lawv muaj li ntawm lipid bilayer. Cov molecules loj, polar molecules thiab them ions tsis tuaj yeem hla qhov teeb meem no. Piv txwv li, channel proteins tsim cov channel rau me me molecules kom diffuse los ntawm (facilitated diffusion).

Dab tsi 3 molecules tsis tau yooj yim dhau los ntawm daim nyias nyias?

Me me uncharged polar molecules , zoo li H2O, kuj tuaj yeem diffuse los ntawm daim nyias nyias , tab sis loj dua uncharged polar molecules , xws li qabzib, ua tsis tau . Them nqi molecules , xws li ions, tsis tuaj yeem sib txawv dhau phospholipid bilayer tsis hais qhov loj me; txawm H+ ions ua tsis tau hla lub lipid bilayer los ntawm kev nthuav tawm dawb.

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