Calculate the energy required for, or released in, a transport of 20 Na+ ions and of 100 molecules of glucose into a biological cell at 37 oC if the membrane potential is –50 mV (negative inside the cell), the concentrations of Na+ and glucose inside the cell are 0.001mol L-1 and 0.01mol L-1 consequently and the concentrations of Na+ and glucose outside of the cell are 0.1mol L-1 and 0.001mol L-1 consequently.

Calculate the energy required for, or released in, a transport of 20 Na+ ions and of 100 molecules of glucose into a biological cell at 37 oC if the membrane potential is –50 mV (negative inside the cell), the concentrations of Na+ and glucose inside the cell are 0.001mol L-1 and 0.01mol L-1 consequently and the concentrations of Na+ and glucose outside of the cell are 0.1mol L-1 and 0.001mol L-1 consequently.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 3SQE

See similar textbooks

Similar questions

One of the important uses of the Nernst equation is in describing the flow of ions across plasma membranes. Ions move under the influence of two forces: the concentration gradient (given in electrical units by the Nernst equation) and the electrical gradient (given by the membrane voltage). This is summarized by Ohms law: Ix=Gx(VmEx) which describes the movement of ion x across the membrane. I is the current in amperes (A); G is the conductance, a measure of the permeability of x, in Siemens (S), which is I/V;Vm is the membrane voltage; and Ex is the equilibrium potential of ion x. Not only does this equation tell how large the current is, but it also tells what direction the current is flowing. By convention, a negative value of the current represents either a positive ion entering the cell or a negative ion leaving the cell. The opposite is true of a positive value of the current. a. Using the following information, calculate the magnitude of Na [ Na+ ]0=145mM,[ Na+ ]i=15mM,Gna+=1nS,Vm=70mV b. Is Na+ entering or leaving the cell? c. Is Na+ moving with or against the concentration gradient? Is it moving with or against the electrical gradient?
Calculate the free energy of transport for the movement of potassium by the sodium/potassium pump under normal physiological conditions: 4 mM serum potassium, 135 mM intracellular potassium, 37.1 °C, and resting potential -82 mV. Express your answer in kJ/mol. Show all work. Calculate the free energy of transport for the movement of potassium by the sodium/potassium pump under disturbed conditions of 2 mM serum potassium. Assume all other parameters remain the same. Express your answer in kJ/mol. Show all work. What factors could limit the continued action of the sodium/potassium pump when only 2 mM potassium is present in the blood plasma? Note that under normal physiological conditions, the cell interior contains 11 mM sodium and the blood contains 140 mM sodium.
37.Given an intracellular concentration of 120mM and an extracellular concentration of 15mM, calculate the Nernst Equilibrium Potential for K+ in mV 38 Given an intracellular concentration of 2mM and an extracellular concentration of 107mM, calculate the Nernst Equilibrium Potential for Cl- in mV 39 A cell has an actual membrane potential (Em) at rest of -75mV. The equilibrium potential for Na+ is +120mV and the equilibrium potential for K+ is -95mV. Calculate the net driving force for Na+ in 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 (−). Membrane permeable only to Cl−.
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+.
a)The distribution of sodium ions across the cell membrane of a neuron is 20 mmol/L inside the cell and 200 mmol/L outside the cell. When the system reaches equilibrium, the concentration of sodium ions will be identical on both sides of the cell membrane. What is the standard Gibbs energy difference in the system? Assume the system is at body temperature (37 °C). b)What is the Gibbs energy difference across the membrane in the initial state (prior to reaching equilibrium)?
Calculate the maximum ratio that can be achieved by the plasma membrane Na+-glucose symporter of an epithelial cell when [Na+]in is 12 mM, [Na+]out is 145 mM, the membrane potential is −50 mV (inside negative), and the temperature is 37 °C.
Calculate the equilibrium membrane potentials to be expected across a membrane at 37 °C, with a NaCl concentration of 0.10 M on the “right side” and 0.01 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+ (b) Membrane permeable only to Cl– (c) Membrane equally permeable to both ions
Calculate the equilibrium membrane potentials to be expected across a membrane at 37 ∘C, with a NaCl concentration of 0.50 M 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 (−). Membrane equally permeable to both ions.
The resting membrane potential of a neuron at 37°C is –60 mV (inside negative). If the freeenergy change associated with the transport of Na+ from o utside to in side is –10.0 kJ/mol, and [Na+]outside the cell is 260 mM, what is [Na+] inside the cell?gas constant R=8.315 J/mol.K; Faraday constant F=96.5 kJ/mol.volt
Estimate the flux (mg/cm2/s) by diffusion of estrogen (a steroid) through a lipid bilayer cell membrane when assuming the diffusion coefficient for estrogen across the lipid bilayer is 10^–6 cm2/s, and that the initial concentration of estrogen in the extracellular fluid is 1 ng/mL and 0 in the cytoplasm.
Calculate the membrane potential in the transport of Cl- from the intracellular environment to the extracellular environment. The Cl- concentration outside the cell is 98 uM, the Cl- concentration in the cytoplasm is 0.025 mM, the Gibbs free energy is -956 J/mol and the temp is 37°C. Have concentration in uM units when solving.