Bernard Katz (March 26, 1911 - April 20, 2003) was a German biochemist. He studied medicine at the University of Leipzig. He graduated in 1934 and fled to England in 1935, the rise of Hitler having made his Russian Jewish heritage dangerous. He was naturalized in 1941. He joined the Royal Australian Air Force and spent the war in the Pacific as a radar officer. His research uncovered fundamental properties of synapses, the junctions across which nerve cells signal to each other and to other types of cells. By the 1950s, he was studying the biochemistry and action of acetylcholine, a signaling molecule with which synapses linking "motor nerves" to muscles stimulate contraction. Katz won the Nobel for his discovery that neurotransmitter release at synapses is quantal (the amount of neurotransmitter released is never less than a certain amount, and if more is always an integral number times this amount). He shared the Nobel Prize in physiology or medicine in 1970 with Julius Axelrod and Ulf von Euler and was also knighted. He died in 2003 at the age of 92.