Let's say you have neurons in a petrie dish bath in a solution in which the extracellular K+ concentration is 5 mM and the intracellular concentration is 100 mM. Now you flood the dish with a solution containing K+ at 115 mM. What will be the Equilibrium Potential now for the cell (rounded up to the next integer)? O O mv O 4 mv O 70 mv O -70 mv

Let's say you have neurons in a petrie dish bath in a solution in which the extracellular K+ concentration is 5 mM and the intracellular concentration is 100 mM. Now you flood the dish with a solution containing K+ at 115 mM. What will be the Equilibrium Potential now for the cell (rounded up to the next integer)? O O mv O 4 mv O 70 mv O -70 mv

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The options for all 8 are either: Depolarization, Na+ influx into cell Vm=-70mV inactivation of voltage-gated Na+ channels and opening of voltage-gated K+ channels Vm = -55mV, voltage Gated Na+ channels open graded potentials stimulating depolarization at the axon hillock hyperpolarization Repolarization, K+ efflux out of cell cells return to resting membrane potential
Suppose that in a certain neuron, negatively charged protein molecules found in the intracellular compartment were suddenly able to diffuse through the cell membrane freely. What would be the result on this cell's resting membrane potential and action potential threshold? A) The resting potential would hyperpolarize and the action potential threshold would not change. B) The resting potential would depolarize and the action potential threshold would decrease. C) The resting potential would depolarize and the action potential threshold would not change. D) The resting potential would hyperpolarize and the action potential threshold would increase.
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 -40 mV?
You have a semi permeable membrane with a membrane potential of -90mV. You also have two ions that are both permeable to the membrane, Na and Cl. Na has a concentration of 10mM inside the membrane and 120mM outside the membrane. Cl has a concentration of 1.5mM inside the membrane and 77.5mM outside the membrane. Use the nernst equation to calculate the electrochemical equilibrium of both ions, and show in which direction the netflux would be for each ion.
Fill in the diagram, your illustration should demonstrate for each phase of the AP: 1. The relative concentration of K and Na 2. The relative voltage across the membrane 3. Any movement across the membrane of K and NA 4. The three kinds of channels in the membrane, and their state (open or closed) 5. Finally, indicate on the graph of the AP which phases correspond to hyper- polarization and which phases correspond to de- polarization Outside Outside Inside Inside Outside Inside Outside 1 Outside Inside Inside
Draw the current that you would expect to flow during a voltage clamp experiment on a typical neuron. Voltages and time course are shown. Briefly explain why the currents are inward or outward. Be sure to provide scale bars. You should definitely label the Y axis so that the peak current value is obvious. Draw the Na+ current you would expect if there were physiological ionic gradients. Draw the K+ current you would expect if there are physiological ionic gradients. Draw the K+ current you would expect if the bath solution and the intracellular solution are both 125 mM.
How does the movement of ICF K+ ions down its concentration gradient affect membrane potential?
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.
What is the equilibrium membrane potential due to Na+Na+ ions if the extracellular concentration of Na+Na+ ions is 138 mM138 mM and the intracellular concentration of Na+Na+ ions is 21 mM21 mM at 20 ∘C20⁢ ∘C ?
The voltage produced by a single nerve or muscle cell is quite small, but there are many species of fish that use multiple action potentials in series to produce significant voltages. The electric organs in these fish are composed of specialized disk-shaped cells called electrocytes. The cell at rest has the usual potential difference between the inside and the outside, but the net potential difference across the cell is zero. An electrocyte is connected to nerve fibers that initially trigger a depolarization in one side of the cell but not the other. For the very short time of this depolarization, there is a net potential difference across the cell, as shown. Stacks of these cells connected in series can produce a large total voltage. Each stack can produce a small current; for more total current, more stacks are needed, connected in parallel. In an electric eel, each electrocyte can develop a voltage of 150 mV for a short time. For a total voltage of 450 V, how many electrocytes must…
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 0 mV?
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+.