Caption:An E. coli cell is about 0.5 microns in diameter and 1.5microns long. Proteinaceous fibers called flagella rotate to propel or stop the cell. The shoter pili aid in sexual conjugation and may help E. coli cells adhere to surfaces. The periplasmic space is an aquous compartment separating the plasma membrane and the outer membrane. Notes:E. coli is (a) gram-negative and (b) a prokaryote. These designations are based on (a) the presence of the outer membrane that does not allow gram stain to bind and (b) the absence of a nucleus.
