Problems
17.1 Why do rod cells respond to light?
17.2 What are the roles of GMP and transducin in vision?
17.3 What is the initial light-induced structural change in bacteriorhodopsin?
17.4 Why does the absorption spectrum of rhodopsin change as the photocycle proceeds?
17.5 How does the isomerization of retinal differ in rhodopsin and bacteriorhodopsin?
17.6 How was FTIR used to characterize the photocycle of bacteriorhodopsin?
17.7 Why was electron microscopy used for the initial determination of the structure of
bacteriorhodopsin rather than protein crystallography?
17.8 How is phase determination different for electron microscopy compared to X-ray diffraction?
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