< Question 6 of 14 > O Macmillan Learning A section of membrane with an aquaporin (AQP) has a water transport rate of about 3 billion water molecules per second 3 x 10 molecules-s-¹). Removal of the AQP lowers the rate to about 40 million water molecules per second ( 4.0 x 107 molecules-s-¹). By what factor does the aquaporin increase the rate of water transport in this example? Note that this is a hypothetical situation, and does not reference any specific data or study. However, 3 x 10° molecules/s is a common estimate given for flow through an AQP. Water flow through an AQP is often stated in terms of a water permeability coefficient with units of centimeters per second. The actual value varies with osmotic pressure and type of AQP, among other factors. Some studies have shown around a 10-fold decrease in water permeability after AQP removal. factor increase:

< Question 6 of 14 > O Macmillan Learning A section of membrane with an aquaporin (AQP) has a water transport rate of about 3 billion water molecules per second 3 x 10 molecules-s-¹). Removal of the AQP lowers the rate to about 40 million water molecules per second ( 4.0 x 107 molecules-s-¹). By what factor does the aquaporin increase the rate of water transport in this example? Note that this is a hypothetical situation, and does not reference any specific data or study. However, 3 x 10° molecules/s is a common estimate given for flow through an AQP. Water flow through an AQP is often stated in terms of a water permeability coefficient with units of centimeters per second. The actual value varies with osmotic pressure and type of AQP, among other factors. Some studies have shown around a 10-fold decrease in water permeability after AQP removal. factor increase:

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

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter3: The Plasma Membrane And Membrane Potential

Section: Chapter Questions

Problem 2SQE: One of the important uses of the Nernst equation is in describing the flow of ions across plasma...

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1. Consider a cell with surface area 2.5 x 102 mm, initial water potential of -0.3MPA and membrane hydraulic conductance of 10 m s MPa". The cell is placed in freshwater having a solute potential of -0.15 MPa. (a) Calculate the driving force for water movement into the cell. (b) Determine the initial flow rate of water into the cell in volumetric terms.
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1:58 l 5GE Done 11 of 23 3 of 12 During an investigation on membrane transport, a researcher exposed bacterial cells to different concentrations of two different solutes: A and B. The rate of transport of each solute into cells is represented in the graph. = Solute A = Solute B Solute Concentration Which of the following best explains the greater rate of transport for solute A than for solute B at higher solute concentrations? Solute A is being transported by simple diffusion, which does not rely on membrane proteins to control the rate of transport. A Solute A is being transported by active transport, which uses ATP and has higher rates of transport than passive transport. B Solute A is being transported by facilitated diffusion, which uses membrane proteins to increase the rate of transport. Submit !! Rate of Transport II
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