Bruce Alberts received his PhD from Harvard University and is Professor of Biochemistry and Biophysics at the University of California, San Francisco. For 12 years, he served as President of the U.S. National Academy of Sciences (1993-2005). Karen Hopkin received her PhD in biochemistry from the Albert Einstein College of Medicine and is a science writer in Somerville, Massachusetts. She is a regular columnist for The Scientist and a contributor to Scientific American's daily podcast, "60-Second Science." Alexander Johnson received his PhD from Harvard University and is Professor of Microbiology and Immunology and Director of the Biochemistry, Cell Biology, Genetics, and Developmental Biology Graduate Program at the University of California, San Francisco. David Morgan received his PhD from the University of California, San Francisco , and is Professor of the Department of Physiology as well as the Vice Dean for Research for the School of Medicine at UCSF Martin Raff received his MD from McGill University and is at the Medical Research Council Laboratory for Molecular Cell Biology and the Biology Department at University College London. Keith Roberts received his PhD from the University of Cambridge and is Emeritus Professor at the University of East Anglia, Norwich. Peter Walter received his PhD from The Rockefeller University in New York and is Professor and Chairman of the Department of Biochemistry and Biophysics at the University of California, San Francisco, and an Investigator of the Howard Hughes Medical Institute.