In what way do the various membranes of a eukaryotic cell differ? Phospholipids are found only in certain membranes. Certain proteins are unique to each membrane. Only certain membranes of the cell are selectively permeable. Only certain membranes are constructed from amphipathic molecules. Some membranes have hydrophobic surfaces exposed to the cytosol, while others have hydrophilic surfaces facing the cytosol. According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly spread in a continuous layer over the inner and outer surfaces of the membrane. confined to the hydrophobic core of the membrane. embedded in a lipid bilayer. randomly oriented in the membrane, with no fixed inside-outside polarity. free to depart from the fluid membrane and dissolve in the surrounding solution. Which of the following factors would tend to increase membrane fluidity? a greater proportion of unsaturated phospholipids a lower temperature a relatively high protein content in the membrane a greater proportion of relatively large glycolipids compared to lipids having smaller molecular weights a high membrane potential Which of the following processes includes all others? osmosis diffusion of a solute across a membrane facilitated diffusion passive transport transport of an ion down its electrochemical gradient Based on the model of sucrose uptake in FIGURE 8.18, which of the following experimental treatments would increase the rate of sucrose transport into the cell? decreasing extracellular sucrose concentration decreasing extracellular pH decreasing cytoplasmic pH adding an inhibitor that blocks the regeneration of ATP adding a substance that makes the membrane more permeable to hydrogen ions Why do phospholipids tend to...