Na and K conductance

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Na and K conductance

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simi
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06/29/07 - 07:36 AM

A trip tp the planet Mars leads to discovery of single cell organisms not found on planet earth.These creatures have a resting membrane potential of +100mV.These organisms have sodium potassium pump but strangely enough Na is pumped into the cell and K is pumped out.The intracellular concentration of Na is 140 mmol/L and intracellular concentration of K is 4mmol/L.These organisms are found swimming in an aqueous solution containing 14mmol/L Na and 300mmol/L K.What is the relation between Na conductance and K conductance in these organisms during resting conditions,assuming that other ions do not have a significant role in establishing resting membrane potential and that the basic principles of elctro physiology apply to Mars creatures.

a)Cannot be determined with available data.

b)K conductance exceed Na conductance

c)K conductance is zero.

d)Na conductance exceeds K conductance

e)Na is equal to potassium conductance.

Please answer with explanation grin

paganini
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06/29/07 - 08:15 AM

in these cells resting membrane potential is close to na+ but since only k+ channels are permeable during resting condition then k+ conductance exceeds that of na+. Ans. b

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new_n_lost
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06/29/07 - 08:16 AM

b)K conductance exceed Na conductance

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paganini
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06/29/07 - 08:49 AM

new_n_lost you recommended in another post to read kaplan phys 2007, is there a significant difference between this and 2004?

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SILVER
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06/29/07 - 09:35 AM

b)K conductance exceed Na conductance

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new_n_lost
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06/29/07 - 03:32 PM

paganini wrote:
new_n_lost you recommended in another post to read kaplan phys 2007, is there a significant difference between this and 2004?

Well i havent read the Kaplan '07 but after doing the Kaplan Physio Qbank Which is Ganong Oriented. According to their Site They have Upgraded their Physio so i m assuming htat they have incorporated Ganong into it. I really cant say tht if there is a difference in the 2 versions.

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paganini
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06/29/07 - 05:16 PM

ok thanks

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