Glycophorin is a 128 amino acid integral membrane protein found onmammalian red blood cells.

It crosses the membrane one time and the amino terminal (-NH3) endof the protein is glycosylated and projects from the external faceof the plasma membrane.

The C-terminal end of the protein (-COOH) projects into thecytoplasm.

a. Sketch a membrane containing glycophorin, showingthe glycosylalted and nonglycosylated ends of the protein.

b. Identify the hydrophilic and hydrophobic regions ofglycophorin in your diagram.

c. Why is it likely that this protein cannot slip out of themembrane and dissolve in the cytoplasm of the cell or in theextracellular fluids?

d. Glycophorin is synthesized in association with theendoplasmic reticulum and, as it is synthesized the amino terminalend of the protein projects into the lumen of the ER.