05 March 1999
Vol 283, Issue 5407

About The Cover

Cover image expansion

COVER Pancreatic cell mitochondrion (~2 micrometers in length). This classic image, captured by pioneering electron microscopist Keith R. Porter (1912-1997), reveals the organelle's highly folded inner membrane. Interest in mitochondria, the cell's "powerhouse," has been invigorated by new discoveries relating to their role in cell death, human disease, evolution, and energy metabolism (see the special section beginning on p. 1475.[Image: K. R. Porter/Photo Researchers, Inc.]