Assuming a typical EPSP of 0.5mV, approximately how many simultaneous EPSP's would be required to bring a typical neuron to threshold?

Separately, draw a table using arrows to depict the appropriate magnitude and direction of the forces and ion fluxes at different membrane potentials for a ligand-gated channel that is equally permeable to both ion X+ and ion Y+.   The equilibrium potential for ion X+ is -60 mV, and the equilibrium potential for ion Y+ is -20 mV.   Which item best represents the forces and fluxes for a membrane potential of -60 mV? Pick one of the four tables in the included image please for your answer.

Conditions: [Na+] outside = .3 mM [Na+] inside the presynaptic cell = .01 mM [dopamine] inside = .5 mM [dopamine] outside = .001 mM ΔGinward = RT ln [X] inside/[X] outside + z F Vm F = 23,000 cal/mol  V R = 1.987 cal/ mol K Membrane potential is .07 V Temperature is 273 K   Using the attachment the information provided, please answer the following questions :   Using what you know about transport across membranes, would the movement of sodium INTO the cell be active or passive?  SHOW your work.   2. Using all of this information, how could you explain how dopamine can re-enter the presynaptic cell – i.e. where does the energy come from?  Use the information in this question to formulate your answer.

Calculate the equilibrium membrane potentials to be expected across a membrane at 37 ∘C, with a NaCl concentration of 0.50M on the "right side" and 0.08 M on the "left side", given the following conditions. In each case, state which side is (+) and which is (−). (a)Membrane permeable only to Na+.

nswer After an action potential is generated in a neuron, it travels to the end of the axon. Explain how the absolute refractory period prevents the action potential from travelling back to the cell body, and why it does not prevent the action potential from moving down to the end of the axon. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac). BIUS Paragraph 启 Q Arial 10pt A Ix ...

Calculate: The equilibrium potential for potassium at room temp  The equilibrium potential for sodium at room temp  Resting membrane potential of this neuron at room temperature

Two branching dendritic arbors are stimulated at the same exact time at locations A & B which are both 10 um away from the axon hillock. Upon stimulation, location A depolarizes 20 mV and location B depolarizes 15 mV. The time constant is the same in both dendrites. The length constant in both dendrites is 10 um. The RMP is -70 mV and the threshold to fire an action potential is -55 mV. Based on the above information, does the neuron fire an action potential? Explain your answer.