Gertrude Falk (August 24, 1925 – March 9, 2008) was an American physiologist, who was Professor of Physiology at University College London, and the first woman to work in her field at UCL Medical School. Born to immigrant parents in the United States, she was the first in her family to enroll at University, earning Bachelor of Science and Doctor of Philosophy degrees. Falk worked at the University of Illinois College of Medicine, University of Washington and UCL Medical School. She and neuroscientist Paul Fatt researched celluar biophysics to find how the retina converts light into electrical signals, and later worked alongside Jonathan Ashmore in demonstrating that light responses can be increased significantly at the synthase between the rod bipolar cell and photoreceptor cell.