Which statements are true? Explain why or why not.1 Transport by transporters can be either active orpassive, whereas transport by channels is always passive.2 Transporters saturate at high concentrations ofthe transported molecule when all their binding sites areoccupied; channels, on the other hand, do not bind theions they transport and thus the flux of ions through achannel does not saturate.3 The membrane potential arises from movementsof charge that leave ion concentrations practically unaf-fected, causing only a very slight discrepancy in the num-ber of positive and negative ions on the two sides of themembrane.

Which statements are true? Explain why or why not.1 Transport by transporters can be either active orpassive, whereas transport by channels is always passive.2 Transporters saturate at high concentrations ofthe transported molecule when all their binding sites areoccupied; channels, on the other hand, do not bind theions they transport and thus the flux of ions through achannel does not saturate.3 The membrane potential arises from movementsof charge that leave ion concentrations practically unaf-fected, causing only a very slight discrepancy in the num-ber of positive and negative ions on the two sides of themembrane.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter5: Membranes And Transport

Section: Chapter Questions

Problem 13TYK

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Uniporters and ion channels support facilitated transport across cellular membranes. Although both are examples of facilitated transport, the rates of ion movement via an ion channel are roughly 104- to 105-fold faster than the rates of molecule movement via a uniporter. What key mechanistic difference results in this large difference in transport rate? What contribution to free energy (ΔG) determines the direction of transport?
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( Notes 1.Explain what will happen to an animal cell when it is placed in a solution that has a greater solute concentration than that inside the cell. 2.How will a plant cell that is subjected to a solute concentration that is less than that of inside the cell will react? 3.What is the importance of the concentration gidient in passive transport? 4.in which type of transport does the working mechanism of a sodium-potassium pump belongs to? Explain, 5.How do secretory cells perform exocytosis?
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