© Macmillan Learning A outside → Ainside, is 10.9 kJ/mol at 25°C. Consider a uniport system where a carrier protein transports an uncharged substance A across a cell membrane. Suppose that at a certain ratio of [A] inside to [A] outside, the AG for the transport of substance A from outside the cell to the inside, What is the ratio of the concentration of substance A inside the cell to the concentration outside? [A]inside [A] outside -81.28 Incorrect Answer Choose the true statement about the transport of A under the conditions described. Decreasing the concentration of the uniport protein in the membrane will cause AG to become a smaller positive number. Because AG is positive, the ratio [A] inside/[A] outside must be less than one. Increasing [A] outside will cause AG for movement of Aoutside to Ainside to become a larger positive number. Movement of Ainside to Aoutside will be spontaneous. Incorrect Answer

water potential  a) At 20°C, a cell containing 0.6M glucose is in equilibrium with its surrounding solution containing 0.5M glucose in an open container.  What is the cell’s ΨP?  b) At 20°C, a cell with ΨP of 3 bars is in equilibrium with the surrounding 0.4M solution of sucrose in an open beaker.  What is the molar concentration of sucrose in the cell?

You are given a pure protein sample to characterize and provided the following information: Its molar extinction coefficient, ε280, is 0.25 liters micromole-1 cm-1 in both the folded and unfolded form            Its ΔGo for unfolding is 1.5 kcal/mol at 37o  (where RT = 0.59 kcal/mole) A) Using a 0.5 cm pathlength cell, you measure the absorbance at 280 nm of a 20-fold dilution of your pure protein in solution (by this, we mean that 50 ul of the protein sample was diluted to a final volume of 1 ml) and find A280 = 0.40. What is the original concentration of the protein before dilution? B) What is the concentration of the unfolded form of the protein in your sample?

At Electrochemical Equilibrium, which best describes the distribution of ions in the chamber, on either side of the membrane, when one "mole" of salt (NaCl) is added to one side of a 1 liter chamber, filled with water and divided in half by a membrane permeable only to Na+. 2.0 M CI- and 1.25 M Na+ one side of the membrane; 0.75 M Na+ on the other side of the membrane. 1.0 M CI- and 1.0 M Na+ on both sides of the membrane. 2.0 M CI- and 1.0 M Na+ one side of the membrane; 1.0 M Na+ on the other side of the membrane. 2.0 M CI- and 2.0 M Na+ on one side of the membrane; pure water on the other side of the membrane.

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.

Suppose the concentration of glucose inside a cell is 0.1 mM and the cell is suspended in a glucose solution of 0.01 mM. (a) What would be the free energy change involved in transporting 10-6 mole of glucose from the medium into the cell? Assume T = 37 °C. (b) What would be the free energy change involved in transporting 10-6 mole of glucose from the medium into the cell if the intracel- lular and extracellular concentrations were 1 mM and 10 mM, respectively? (c) If the processes described in parts (a) and (b) were coupled to ATP hydrolysis, how many moles of ATP would have to be hydrolyzed in order to make each process favorable? (Use the standard free energy change for ATP hydrolysis.)

A spherical cell with the diameter of 10uMhas a protein concentration of 20 mg/ml. Determine the number of protein molecules within the cell if the molecular weight of an average protein is 50,000 daltons (g/mol). Recall that Avogadro's number is NA 6.0221367×1023 molecules/mol. =

Neutral sphingomyelinase 2 converts sphingomyelin into ceramide and phosphorcholine. What kind of enzyme is it? Assume Vmax is 35 µM min-1. When you provide 3.0 x 10-5 M of sphingomyelin, you observe an initial velocity of 6.0 µM min-1. Calculate the KM.

Please asap with explanation

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