(Solved): HELP!! 1. What is chemiosmotic coupling and how is it used by cells to produce ATP? 2. What is redox ...

1. What is chemiosmotic coupling and how is it used by cells to produce ATP? 2. What is redox potential and how is it used in electron transport chanis? 3. What two ways do plant cells use to synthesize ATP? 4. Lipid bilayers are considered to be two-dimensional fluids; what does this mean? What factors affect the degree of membrane fluidity? 5. Explain the following statement. The structure of all biomembranes depends on the chemical properties of phospholipids, whereas the function of each specific biomembrane depends on the specific proteins associated with that membrane. 6. Uniporters and ion channels support facilitated diffusion across biomembranes. Although both are examples of facilitated diffusion, the rates of ion movement via an ion channel are roughly \( 10^{4} \) - to \( 10^{5} \)-fold faster than that of molecules via a uniporter. What key mechanistic difference results in this large difference in transport rate? 7. The neurotransmitter acetylcholine is made in the cytosol and then transported into synaptic vesicles, where its concentration is more than 100 -fold higher than in the cytosol. When synaptic vesicles are isolated from neurons, they can take up additional acetylcholine added to the solution in which they are suspended, but only when ATP is present. \( \mathrm{Na}^{+} \)ions are not required for acetylcholine uptake, but curiously, raising the \( \mathrm{pH} \) of the solution in which the synaptic vesicles are suspended increased the rate of acetylcholine uptake. Furthermore, transport is inhibited when drugs are added that make the membrane permeable to \( \mathrm{H}^{+} \)ions. Suggest a mechanism that is consistent with all of these observations.