Video: Lub peev xwm membrane ua li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Yuav luag txhua plasma daim nyias nyias muaj hluav taws xob peev xwm hla lawv, nrog rau sab hauv feem ntau tsis zoo nrog rau sab nraud. Cov membrane muaj peev xwm muaj ob txoj haujlwm yooj yim. Ua ntej, nws tso cai rau lub xov tooj ntawm tes ua haujlwm ua lub roj teeb, muab lub zog los ua haujlwm ntau yam ntawm "cov khoom siv molecular" embedded hauv daim nyias nyias.
Tsis tas li ntawd, lub peev xwm membrane yog dab tsi thiab vim li cas nws tseem ceeb?
Muaj nuj nqi. Qhov tseem ceeb ntawm cov so membrane muaj peev xwm yog tias nws tso cai rau lub cev excitable hlwb (neurons thiab cov leeg) kom muaj kev hloov pauv sai los ua lawv lub luag haujlwm kom raug.
Yuav ua li cas yog lub membrane muaj peev xwm tswj tau? Sodium-poov tshuaj twj tso kua mis txav ob lub poov tshuaj ions nyob rau hauv lub cell raws li peb sodium ions yog pumped tawm mus tswj tus nqi tsis zoo daim nyias nyias nyob rau hauv lub cell; qhov no pab tswj tus so peev xwm.
Yog li ntawd, qhov zoo ntawm daim nyias nyias txhais li cas?
Yog tias membrane muaj peev xwm ua ntau zoo tshaj nws yog nyob rau so peev xwm , cov daim nyias nyias hais tias depolarized. Yog tias membrane muaj peev xwm ua tsis zoo ntau dua li nws nyob ntawm so peev xwm , cov daim nyias nyias hais tias yog hyperpolarized.
Yuav ua li cas thaum lub sij hawm so membrane?
Qhov (a) so membrane muaj peev xwm yog qhov tshwm sim ntawm qhov sib txawv ntawm Na+ thiab K+ ions sab hauv thiab sab nraud ntawm tes. Tus nqi tsis zoo nyob rau hauv lub cell yog tsim los ntawm lub cell daim nyias nyias ua permeable rau poov tshuaj ion zog ntau dua li sodium ion zog.
Pom zoo:
Yuav ua li cas so membrane muaj peev xwm tsim thiab khaws cia?
Qhov tsis zoo ntawm cov ntaub so ntswg yog tsim thiab tswj los ntawm kev ua kom cov concentration ntawm cations sab nraum lub cell (hauv cov kua dej extracellular) txheeb ze rau hauv lub cell (hauv cytoplasm). Cov kev ua ntawm sodium potassium twj tso kua mis pab tswj lub peev xwm so, ib zaug tsim
Dab tsi yog qhov txawv ntawm electrostatic muaj peev xwm thiab electrostatic muaj peev xwm zog?
Tsis muaj qhov sib txawv ntawm electrostatic potentialenergy thiab hluav taws xob (al) muaj peev xwm zog. Lub peev xwm hluav taws xob ntawm ib qho taw tes yog kev ua haujlwm los ntawm lwm qhov kev quab yuam hauv kev txav chav tsev zoo los ntawm ib qho arbitrarilychosen xoom ntawm lub peev xwm (feem ntau infinity) mus rau lub ntsiab lus
Puas muaj peev xwm hluav taws xob thiab lub zog muaj peev xwm tib yam Vim li cas lossis vim li cas ho tsis?
Lub zog muaj peev xwm hluav taws xob Ue yog lub zog muaj peev xwm khaws cia thaum cov nqi tawm ntawm qhov sib npaug (xws li lub zog muaj peev xwm gravitational). Lub peev xwm hluav taws xob zoo ib yam, tab sis ib tus nqi, Ueq. Ib qho hluav taws xob muaj peev xwm sib txawv ntawm ob lub ntsiab lus hu ua voltage, V = Ue2q−Ue1q
Dab tsi yog cov qauv ntawm lub zog nyob rau hauv lub peev xwm thiab lub zog kinetic?
Lub zog muaj peev xwm yog khaws cia lub zog thiab lub zog ntawm txoj haujlwm - lub zog gravitational. Muaj ntau hom kev muaj peev xwm muaj zog. Kinetic zog yog kev txav - ntawm nthwv dej, electrons, atoms, molecules, tshuaj, thiab khoom. Chemical Zog yog lub zog khaws cia hauv cov khoom sib txuas ntawm atoms thiab molecules
Puas muaj peev xwm equilibrium zoo ib yam li so muaj peev xwm?
Qhov sib txawv ntawm daim nyias nyias muaj peev xwm thiab qhov muaj peev xwm sib npaug (-142 mV) sawv cev rau lub zog hluav taws xob hluav taws xob uas tsav Na + mus rau hauv lub xovtooj ntawm lub peev xwm so membrane. Thaum so, txawm li cas los xij, qhov permeability ntawm daim nyias nyias mus rau Na + tsawg heev kom tsuas yog me me Na + xau rau hauv lub cell