3.5 Qu’est-ce qu’elle a fait le weekend dernier? (1)

(3 points) Which of the following conditions results in the fastest FRAP?

(3 points) Which of the following statements about a plot of V0 vs. for transport that follows Michaelis-Menten kinetics is false?   

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below. Not all words or phrases will be used; use each word or phrase only once. (7 points) The specialized functions of different membranes are largely determined by the _____________ they contain. Membrane lipids are _______________ molecules, composed of a hydrophilic portion and a hydrophobic portion. All cell membranes have the same ________________ structure, with the ________________ of the phospholipids facing into the interior of the membrane and the ______________ on the outside. The most common lipids in most cell membranes are the _______________. The head group of a glycolipid is composed of _______________.   amphipathic                              hydrophobic                                 phosphatidylserine cholesterol                                 lipid bilayer                                   phospholipids fatty acid tails                           lipid monolayer                           proteins glycolipids                                   lipids                                                 sterols hydrophilic head groups    phosphatidylcholine                sugars

(3 points) Why do cells not have membrane transport proteins for O2?  

3.6 Qu’est-ce qu’elle fait dans le jardin? Donne deux détails (2)

    (3 points) Proteins extracted from control cells, cells treated with trypsin, and permeabilized cells treated with trypsin are examined using SDS- Polyacrylamide Gel Electrophoresis (SDS-PAGE). Based on the analysis of the SDS PAGE studies, scientists concluded that:

(3 points) The lateral diffusion of a plasma membrane protein has been studied using the fluorescence recovery after photobleaching (FRAP) technique in a cell under normal conditions, and the following plot has been obtained. Under a different condition, membrane protein complexes disassemble freeing partially-immobilized protein components. As a result, its lateral diffusion coefficient is increased. How would you expect the FRAP curve to change under these new conditions? The dotted line in each graph is the original curve shown for comparison.

(3 points) Many amino acids in our diet are absorbed via the transcellular transport pathway by the intestinal epithelial cells. This process requires ATP hydrolysis by …

(5 points) Gastric acid is produced by parietal cells in the stomach. Its secretion is a complex and relatively energetically expensive process that acidifies the stomach with HCl while maintaining a neutral cytosolic pH. Using the space provided, describe the process of acidifying the gastric fluid and (1) describe each one of the 5 transporters shown, and (2) explain their role in creating the acidic gastric pH.