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Your question isn't all that precise but I think looking at individual ionic equilibrium potentials begins to give us some understanding. Looking at the equilibrium potentials(EK for potassium and ENA for sodium) for these two ions and their channels you have that EK = -90mV and ENA = +60mV in a typical neuron. This means that at these voltages you will ...


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Why nature has done it this way around is difficult to explain. What is certain, however, is that the membrane potential which results from the imbalance of these ions across the membrane is used for a variety of purposes, such as transport of other ions and molecules, action potential generation in neurons among many other things. How it is accomplished ...


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There are not much explanations available, as far as I can see. The best explanation that I have found is that the positive charge allows the orientation of the protein in the membrane. The orientation for membrane proteins is important as a lot of them are transporters which have a dedicated transportation direction. The same is true for receptors, which ...


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There are various mechanisms through which membrane proteins can remain localized in the membrane. See the below figure from MBOTC (book): ...


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The book "Basic Histology" by Junqueira and Carneiro acknowledge the problem in histologic fixation of ground substance. They recommend freeze drying in liquid nitrogen and then removing water by high vacuum at a temperature of -30 celcius, which will cause sublimation (ice-->vapor). Then fixing the sample with a nonpolar solvent. Afterwards you can use ...


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Different components of the ECM can be stained differently but since you asked about hyaluronic acid (HA) I'll limit my answer to its staining. See this paper. They use Hyaluran Binding Protein (HABP) as a specific probe for HA. Because HA has a very simple, conserved composition and is ubiquitously expressed in all animals that have a developed ...


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Very nice question! I'll go through your three questions sequentially. Q1: Why does lower capacitance increase "the effectiveness of nearby nodes" or allow the depolarizing voltage to "travel not by ion diffusion, but as an electric field"? A: Capacitance basically results in sequestering of charge of opposite polarities along the cell membrane, which ...


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Excellent question! The difference is the fact that the rheobase is an example of a threshold measure. The threshold, as you correctly suggest, is the minimal energy (typically current level and not voltage as you suggest) to excite neural tissue. The threshold applies only under the specific experimental parameter settings used. These parameters include the ...


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The Hodgkin-Huxley model: $$I=C_m\frac{dV}{dt} + g_k(V_m - V_k) + g_{Na}(V_m - V_{Na}) + g_l(V_m- V_l)$$ Where $C_m$ is membrane capacitance per unit area and $g_i$ are membrane conductances. Reducing the number of channels does not affect capacitance per se (it does in a way) but what it basically does is to reduce membrane conductance to leak channels ...



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