Primary and Secondary Transport Artificial membrane vesicles created in a laboratory were placed in series of aqueous solutions to test primary and secondary active transport systems. The researchers tested a H*/glucose symporter in a variety of conditions and in the presence and absence of a H*-pump. They then measured the internal glucose concentrations. Check all those systems where glucose concentrations are expected to increase. Check All That Apply pH 5.0 0.5 mM Glucose pH 7.0 5 mM ATP 5mM Glucose pH 5.0 0.5 mM Glucose pH 70 0 mM ATP 5 mM Glucose Glucose > Glucose

Primary and Secondary Transport Artificial membrane vesicles created in a laboratory were placed in series of aqueous solutions to test primary and secondary active transport systems. The researchers tested a H/glucose symporter in a variety of conditions and in the presence and absence of a H-pump. They then measured the internal glucose concentrations. Check all those systems where glucose concentrations are expected to increase. Check All That Apply pH 5.0 0.5 mM Glucose pH 7.0 5 mM ATP 5mM Glucose pH 5.0 0.5 mM Glucose pH 70 0 mM ATP 5 mM Glucose Glucose > Glucose

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 6RE

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Similar questions

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 mechanisticdifference results in this large difference in transport rate?What contribution to free energy (ΔG) determines the direction of transport?
The Na+/glucose cotransporter in ION-GRADIENT-DRIVEN ACTIVE TRANSPORT, ________moves down its gradient and _______ against its gradient. Na+/K+ Na+/Na+ Na+/glucose glucose/glucose
Name the three classes of membrane transport proteins. Explain which one or ones of these classes is able to move glucose and which can move bicarbonate (HCO3 −) against an electrochemical gradient. In the case of bicarbonate, but not glucose, the ΔG of the transport process has two terms.What are these two terms, and why does the second not apply to glucose? Why are cotransporters often referred to as examples of secondary active transport?
Name the three classes of membrane transport proteins. Explain which one or ones of these classes is able to move glucose and which can move bicarbonate (HCO3−) against an electrochemical gradient. In the case of bicarbonate, but not glucose, the ΔG of the transport process has two terms. What are these two terms, and why does the second not apply to glucose? Why are cotransporters often referred to as examples of secondary active transport?
Glucose transport across cell membranes varies depending upon blood glucose levels. When glucose levels are high, glucose transport is accomplished via membrane transporters. When glucose concentrations are low, the transport of glucose across the membrane is dependent upon the sodium ion concentration. What types of transport is observed for glucose? A)simple diffusion at high [glucose], secondary active transport at low [glucose] B)facilitated diffusion at high [glucose], secondary active transport at low [glucose] C)simple diffusion at high [glucose], primary active transport at low [glucose] D)facilitated diffusion at high [glucose], primary active transport at low [glucose]
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.
Compare and contrast the different transport mechanisms: Electrochemical gradient Carrier-Mediated/Not Metabolic Energy Na+ Gradient Inhibition of Na-K Pump
• Describe the concept of transport maximum (Tm). • Explain the membrane potential and the equilibrium potential. • What information does the Nernst Equation provide? What is the limitation inherent to the Nernst Potential?
Which is not required for passive transport across a membrane (select all that apply and explain why): a concentration gradient a cotransported ion energy a protein channel
The membrane transport protein Na+-K+ ATPase carries both Na+ and K+ ions across the plasma membrane. Typically the concentration of K+ inside cells is about 30 times higher inside the cell than outside. The concentration of Na+ is about 20 times less inside the cell than outside. Based on this information, which statement below is false? A. The proper functioning of Na+-K+ ATPase could serve as an energy source for secondary active transport proteins. B. It is a symport. C. Transport of Na+ and K+ must be coupled to an exergonic reaction. D. Na+-K+ ATPase likely undergoes conformational changes during transport.
"Transport by transporters can be either active or passive, whereas transport by channels is always passive" is true or false.
The average time it takes for a molecule to diffuse adistance of x cm is given byt = x2/2D where t is the time in seconds and D is the diffusioncoefficient. Given that the diffusion coefficient ofglucose is 5.7 × 10−7cm2/s, calculate the time it wouldtake for a glucose molecule to diffuse 10 μm, which isroughly the size of a cell.