Contents

28 August 2009
Vol 325, Issue 5944

About The Cover

Cover image expansion

COVER Pseudocolored scanning electron micrograph (magnification ~34,000x) of the surface of mouse airway epithelia showing cilia protruding from epithelial cells; short protrusions in the foreground are microvilli from a nonciliated cell. In human airway epithelia, these motile cilia bear receptors that detect bitter compounds and signal the cilia to increase their rhythmic beat frequency to help clear noxious substances from the lungs. See page 1131. Image: Tom Moninger (epithelia generated by Phil Karp)