Homework Help: Animal Physiology-Membrane Potential

Posted by John on Thursday, September 15, 2011 at 11:21am.

Intracellular Extracellular
Na+ 12 mM 160 mM
Cl- 7 mM 110 mM
K+ 140 mM 5 mM

1.How do you calculate the equilibrium potential for potassium, K+, under these conditions?

2. Assuming that Na+ is the only ion the plasma membrane of this cell is permeable to, at what voltage will there be no net flux of any ions? Can you give the equation along with how you go about it?

3.Can you calculate (predict) the resting Vm for a neuron with these ion concentrations above (at 37°C). Assume now that the membrane is 20x more permeable to K+ than to Na+, and 100x more permeable to K+ than to Cl-. Again with the equation first.

4. Why is the Vm of this neuron, calculated in #3, closer to EK+, than to ENa+?

5. Assume now that the plasma membrane of this neuron undergoes a rapid change in ion permeability so that it is now 20x more permeable to Na+ than to K+, and 100x more permeable to Na+ than to Cl-. Predict (calculate) the membrane potential under these conditions. Again with the equation first.

I don't know how to do these problems. I need help severly!

Animal Physiology-Membrane Potential - John, Thursday, September 15, 2011 at 11:36am
For #1, I got E(K+) = 60/+1 * log (5mM/140mM) = -87mV I think this is right but I don't the rest

Answer this Question

Related Questions

math - A circle has a circumference of 110.6 mm. Find its diameter to the ...
Physical Science - Hello, I need some help with the following question. Thank ...
Math 156 - The systolic blood pressures of the patients at a hospital are ...
Physical Science - Hello, Do I have the correct answer for the following ...
math - 1500cm= mm 72 km= m 38000 cm= m 42 m= mm 986 cm= mm 48000 mm= m 5000 m= ...
Geometry HELP - A soccer ball has diameter of 400 mm. A pin is stuck into the ...
geometry - Find the value of ED, if AE = 6 mm, EB = 8 mm, and CE = 12 mm.
dif. bet. Mm and mm - I was just working on a problem and i seem to keep getting...
Maths - Hey! Okay so when the weather reporters say that ?mm of rain fell over ...
bio but acting more like math - okay I am converting some measurements and is 30...

For Further Reading

First Name:
School Subject:
Answer: