Glucose is a large molecule that cannot penetrate the phospholipid bilayer of cells. Instead, glucose enters most cells, such as red blood cells, through special carrier proteins embedded in the surface of the plasma membrane. In doing so, glucose moves from an area of high concentration to an area of low concentration. Based on this information, which term best describe the uptake of glucose by red blood cells?
a. Facilitated diffusion
b. Active transport
c. Glycolysis
d. Osmosis