Video: Nernst muaj peev xwm suav li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Cov peev xwm hla lub cell membrane uas tawm tsam qhov sib txawv ntawm ib qho ion los ntawm daim nyias nyias yog hu ua Nernst muaj peev xwm rau ion. Raws li pom saum toj no, qhov loj ntawm lub Nernst muaj peev xwm yog txiav txim siab los ntawm qhov sib piv ntawm cov concentrations ntawm qhov tshwj xeeb ion ntawm ob sab ntawm daim nyias nyias.
Tom qab ntawd, ib tug kuj yuav nug, yuav ua li cas tus neeg nernst muaj peev xwm txiav txim siab lub peev xwm so membrane?
A so (non-signaling) neuron muaj qhov voltage hla nws daim nyias nyias hu ua so membrane muaj peev xwm , los yog qhov yooj yim so peev xwm . Cov so peev xwm yog txiav txim siab los ntawm concentration gradients ntawm ions thoob plaws lub daim nyias nyias thiab los ntawm daim nyias nyias permeability rau txhua hom ion.
Kuj Paub, vim li cas Nernst kab zauv muaj txiaj ntsig zoo hauv kev cuam tshuam rau cov peev txheej membrane? Cov Nernst equation rau ib tug muab ion txiav txim qhov txawv ntawm peev xwm ntawm ob sab ntawm lub daim nyias nyias ntawm qhov no ion yog nyob ntawm qhov sib npaug ntawm sab hauv thiab sab nraud flux (zero net tam sim no).
Ntxiv mus, nernst xam li cas?
Cov Nernst kev sib npaug xam lub peev xwm equilibrium (tseem hu ua Nernst muaj peev xwm) rau ib qho ion raws li tus nqi ntawm cov ion (piv txwv li, nws cov valence) thiab nws cov concentration gradient thoob plaws hauv daim nyias nyias. Kub kuj cuam tshuam rau Nernst muaj peev xwm (saib Nernst kev sib npaug hauv qab no).
Lub peev xwm sib npaug nyob li cas?
Tus nqi ntawm cov equilibrium muaj peev xwm rau tej ion nyob ntawm Qhov concentration gradient rau qhov ion hla ntawm daim nyias nyias. Yog hais tias cov concentrations ntawm ob sab yog sib npaug, lub zog ntawm cov concentration gradient yuav be zero, thiab equilibrium tej zaum yuav kuj zero.
Pom zoo:
Cov khoom puas muaj ob qho tib si kinetic thiab lub zog muaj peev xwm?
Ib yam khoom muaj peev xwm muaj ob qho tib si kinetic thiab lub zog muaj peev xwm tib lub sijhawm. Piv txwv li, ib yam khoom uas poob, tab sis tseem tsis tau mus txog hauv av muaj lub zog kinetic vim nws txav mus rau hauv qab, thiab lub zog muaj peev xwm vim tias nws muaj peev xwm txav mus rau hauv qab txawm tias nws twb muaj lawm
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
Yuav ua li cas muaj ntau yam genotypes muaj peev xwm rau lub tsho tiv no Xim nyob rau hauv luav?
Plaub qhov sib txawv muaj nyob rau hauv cov xim luav (C) gene
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