3. Cell membranes contain a variety of integral andperipheral membrane proteins.
a. Explain the differences between symport, antiport anduniport proteins compared to ion channels.
b. There are a variety of glucose transport proteins inthe cell membrane with some relying heavily on the sodium/potassiumATPase pump. (1) Explain this relationship and indicate how this isimportant to the translocation of glucose across the intestinallumen into the blood. (2) CHALLENGE: Suggest an in vitroexperiment that would allow you to test this relationship anddetermine in which direction the glucose is transported (e.g.apical to basal vs basal to apical). Hint: See Fig. 11-30 in yourtext and associated text.
c. CHALLENGE: You purify an integral membrane proteinand perform a hydropathy plot. Analysis of this protein shows 7substantial peaks in the 0 to + range. You presume that thisprofile suggests that you may be working with a GPCR. Explain thebasis for your reasoning and explain how you might be able to testthis hypothesis.
