Glucose and sodium can be co-transported across a membrane through the Na/glucose co-transporter. This transporter is us

[answerhappygod]

Glucose And Sodium Can Be Co Transported Across A Membrane Through The Na Glucose Co Transporter This Transporter Is Us 1 (42.66 KiB) Viewed 33 times

2.

Glucose And Sodium Can Be Co Transported Across A Membrane Through The Na Glucose Co Transporter This Transporter Is Us 2 (53.32 KiB) Viewed 33 times

Glucose And Sodium Can Be Co Transported Across A Membrane Through The Na Glucose Co Transporter This Transporter Is Us 3 (57.05 KiB) Viewed 33 times

Glucose and sodium can be co-transported across a membrane through the Na/glucose co-transporter. This transporter is used to transport glucose into cells of the gut epithelium as depicted in the diagram to the right. Remember: the concentration of glucose in the gut lumen is low relative to the intracellular concentration while the levels of Na" within the cell are lower than those in the gut lumen. Na You decide to study the Na/Glucose co-transporter in reconstituted lipid vesicles in which the only protein present is the Na/glucose co-transporter as depicted to the right. For each of the following experimental conditions: glucose (i) Which molecules will be transported across the membrane? (ii) In which direction will the molecules move (out/in)? (iii) Briefly explain. B) Na*: higher outside vesicles, Glucose: higher inside vesicles (4 points) Extracellular space/ gut lumen A) Is the transport of glucose into cells of the gut epithelium an example of active or passive transport? (3 points) Intracellular space O C) Na*: equal concentration inside and outside vesicles, Glucose: higher inside vesicles (4 points) D) In a separate experiment you decide to test what would happen if you replaced the Na* in your system with K. (4 points) K*: higher outside of vesicles, Glucose: higher inside vesicles. (i)Which molecules will be transported and (ii) in which direction will they move? (iii) Briefly explain your answer.
8. Cells use membranes to help maintain set ranges of ion concentrations inside and outside the cell. Which of the following ions is the most abundant inside a typical mammalian cell? (circle one option; 3 points) (a) Na+ (b) K+ (c) Ca2+ (d) Cl- 9. Membrane lipids are capable of many different types of movement. Which of these does not occur spontaneously in biological membranes? switching between lipid layers lateral movement (b) (c) (d) 10. Which of the following is not a general mechanism that cells use to maintain stable patterns of gene expression as cells divide? (a) a positive feedback loop, mediated by a transcriptional regulator that activates transcription of its own gene in addition to other cell-type specific genes faithful propagation of condensed chromatin structures as cells divide inheritance of DNA methylation patterns when cells divide proper segregation of housekeeping proteins when cells divide (b) (c) (d) 11. Transporters, in contrast to channels, work by specific binding to solutes a gating mechanism (a) (b) rotation flexing of hydrocarbon chains (c) (d) (a) (b) (c) (d) filtering solutes by charge filtering solutes by size 12. The advantage to the cell of the gradual oxidation of glucose during cellular respiration compared with its combustion to CO₂ and H₂O in a single step is that_ more free energy is released for a given amount of glucose oxidized no energy is lost as heat energy can be extracted in usable amounts more CO₂ is produced for a given amount of glucose oxidized 13. Antibodies can be used for all of the following except: (a) (b) (c) (d) Determining the subcellular localization of a protein Visualizing a protein in a Western blot Finding the gene that codes for a protein Isolating a known protein of interest from cell lysate
14. Transporters, in contrast to channels, work by (a) specific binding to solutes (b) a gating mechanism (c) filtering solutes by charge (d) filtering solutes by size 15. The advantage to the cell of the gradual oxidation of glucose during cellular respiration compared with its combustion to CO2 and H2O in a single step is that (a) more free energy is released for a given amount of glucose oxidized (b) no energy is lost as heat (c) energy can be extracted in usable amounts (d) more CO2 is produced for a given amount of glucose oxidized 16. T/F The driving force that pulls protons into the matrix is called the proton-motive force, which is a combination of the large force due to the pH gradient and the smaller force that results from the voltage gradient across the inner mitochondrial membrane. 17. T/F Facilitated diffusion occurs only from a region of lower solute concentration to a region of higher solute concentration. 18. T/F During glycolysis, glucose molecules are broken down to yield CO2 and H₂O. 19. (Integral/peripheral membrane) proteins are linked to the membrane through noncovalent interactions with other membrane-bound proteins. 20. For an uncharged molecule, the direction of passive transport across a membrane is determined solely by its (electrochemical/concentration gradient). 21. The action potential is propagated by the opening of (voltage/ligand-gated channels). 22. The resting membrane potential of a neuron is set through the opening of (Na-/K--leak channels).