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Que NO ES una celula:

El potencial de membrana, las pilas, el equilibrio Donnan, la ecuacion de Nernst y la bomba de Na y K. Que NO ES una celula:. no es una pila. no es una pila de concentracion. no es algo en equilibrio Donnan. Una pila de concentracion. Fe2+ 4mM. Fe2+ 100mM. Fe3+ 150mM. Fe3+ 10mM.

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Que NO ES una celula:

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  1. El potencial de membrana, las pilas, el equilibrio Donnan, la ecuacion de Nernst y la bomba de Na y K.

  2. Que NO ES una celula: no es una pila no es una pila de concentracion no es algo en equilibrio Donnan

  3. Una pila de concentracion Fe2+ 4mM Fe2+ 100mM Fe3+ 150mM Fe3+ 10mM E = 0.059 log[(4.10)/(100.150)]= -149 mV

  4. Una celula E  -65 mV [K+] 143 mM [K+] 11mM [Na+] 33.4 mM [Na+] 133mM [Cl-] 144mM [Cl-] 11.5 mM [P-] 165 mM m1K+ = mK+0 + RT ln [K+]1 + FE m2K+ = mK+0 + RT ln [K+]2 si m1K+ = m2K+ E = RT/F ln [K+]2 / [K+]1 = 66 mV

  5. Una celula [K+] 143 mM [K+] 11mM [Na+] 33.4 mM [Na+] 133mM [Cl-] 144mM [Cl-] 11.5 mM [P-] 165 mM PK+ = 1 PNa+ = 0.01 PCl- = 0.1 flujos proporcionales a p y Dm

  6. Una celula mK+0 + RT ln [K+]1 + FE = mK+0 + RT ln [K+]2 mNa+0 + RT ln [Na+]1 + FE = mNa+0 + RT ln [Na+]2 mCl-0 + RT ln [Cl-]1 - FE = mCl-0 + RT ln [Cl-]2 [K+]1 + [K+]2 154 mM [Na+]1 + [Na+]2 166.4 mM [Cl-]1 + [Cl-]2 = 155.5 mM [Cl-]2 = [K+]2 + [Na+]2 es esto electroneutralidad ? NO !

  7. Una celula [K+] 143 mM [K+] 11mM [Na+] 33.4 mM [Na+] 133mM [Cl-] 144mM [Cl-] 11.5 mM [P-] 165 mM La celula es un capacitor electrico

  8. Una celula [K+] 103.8 mM [K+] 50.2mM [Na+] 111.7 mM [Na+] 54.3 mM [Cl-] 104.5 mM [Cl-] 50.5 mM [P-] 165 mM E = -18.6mV este es el potencial Donnan

  9. Entonces, por que no se mide el potencial que calculamos ?

  10. La bomba de Na+ / K+ [K+] 143 mM [K+] 11mM [Na+] 33.4 mM [Na+] 133mM [Cl-] 144mM [Cl-] 11.5 mM [P-] 165 mM 3 Na+ 2 K+ velocidad de bomba = f(ATP)

  11. Como podemos calcularlo ? Valores iniciales [Na],[K],[Cl],E dt FNa(12) = PNa. DmNa + 3fbomba FK(12) = PK. DmK - 2fbomba FCl(12) = PCl. DmCl Modifican valores [Na],[K],[Cl] E = qexc / C (C = capacidad membrana) (qexc = [Na+]+[K+]-[Cl-]-[P-])

  12. Cuando la bomba deja de ser electrogenica ...

  13. Na+ K+ E/mV

  14. Conclusiones: 1 - La Celula es un capacitor que acumula carga a los lados de la membrana. 2 - La carga del capacitor se establece por acción de la bomba de K+/Na+ 3 - La “electroneutralidad” es solamente un concepto para calcular facilmente el potencial.

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