Koj ua li cas xam cov peev xwm thim rov qab?
Koj ua li cas xam cov peev xwm thim rov qab?

Video: Koj ua li cas xam cov peev xwm thim rov qab?

Video: Koj ua li cas xam cov peev xwm thim rov qab?
Video: ua zoo poob peev los lawm tub huas xyooj MV 2023 2024, Kaum ib hlis
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rau ib tug muab ion, lub rov qab muaj peev xwm tuaj yeem xam los ntawm Nernst kev sib npaug qhov twg: R = gas tas li. T = kub (in oK) z = ion charge.

Equilibrium (los yog thim rov qab) muaj peev xwm

  1. ib tug so membrane peev xwm ntawm -12 mV (raws li tsim los ntawm Na+/K+ ATPase)
  2. tsis muaj voltage- lossis ligand-gated channels.
  3. thaum xub thawj, tsis muaj cov pa xau.

Ntawm no, qhov kev thim rov qab txhais tau li cas?

Nyob rau hauv ib tug bio membrane, lub rov qab muaj peev xwm (tseem hu ua Nernst peev xwm ) ib ion yog daim nyias nyias peev xwm nyob ntawd yog tsis muaj net (tag nrho) ntws ntawm qhov tshwj xeeb ion ntawm ib sab ntawm daim nyias nyias mus rau lwm qhov. Equilibrium hais txog qhov tseeb tias cov net ion flux ntawm ib qho hluav taws xob tshwj xeeb yog xoom.

Tsis tas li ntawd, qhov tsis zoo nernst muaj peev xwm txhais tau li cas? (Lub Nernst muaj peev xwm yog qhov voltage qho yuav sib npaug tawm qhov tsis sib npaug ntawm qhov sib npaug ntawm daim nyias nyias rau qhov ion. Ib tug loj tsis zoo Qhov voltage (-90mV) yuav tuav qhov zoo K + ions hauv cell. Cov kev sib tw nyiam, cov nqi zoo sib xws ua rau ib leeg).

Ib yam li ib tug yuav nug, dab tsi yog qhov sib npaug ntawm cov poov tshuaj?

Cov Potassium equilibrium muaj peev xwm E K yog −84 mV 5 mM poov tshuaj sab nraud thiab 140 mM sab hauv. Ntawm qhov tod tes, sodium equilibrium muaj peev xwm , ENa, yog kwv yees li +66 mV nrog kwv yees li 12 mM sodium sab hauv thiab 140 mM sab nraud.

Dab tsi ua rau muaj peev xwm ua tau?

Tej yam peev xwm ua tau yog ua rau thaum sib txawv ions hla lub neuron membrane. Ib qho stimulus ua ntej ua rau sodium channels qhib. Vim tias muaj ntau ntau sodium ions nyob rau sab nraud, thiab sab hauv ntawm cov neuron yog qhov tsis zoo rau sab nraud, sodium ions maj nrawm rau hauv cov neuron.

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