February 1 – Oswald T. Avery and colleagues publish the Avery–MacLeod–McCarty experiment[1] showing that a DNA molecule can carry an inheritable trait to a living organism. This is important because many biologists thought that proteins were the hereditary material and nucleic acids too simple chemically to serve as genetic storage molecules.[2]
The lipopolysaccharide character of enteric endotoxins is elucidated by M. J. Shear.[3]
June 13 – First operational use of the German V-1 flying bomb, the first operational cruise missile, containing a gyroscope guidance system and propelled by a simple pulsejet engine.
September 8 – First operational use of the German V-2 rocket, the first ballistic missile. On June 20 one has become the first man-made object to cross the Kármán line and reach the edge of space.[12]
December 9 – First flight of the Heinkel He 162Volksjäger, the second jet engined fighter aircraft to be introduced by the Luftwaffe in World War II.
^Fruton, Joseph S. (1999). Proteins, Enzymes, Genes: the interplay of chemistry and biology. New Haven, Conn: Yale University Press. pp. 438–440. ISBN0-300-07608-8.
^Shear, M. J. (1944). "Chemical treatment of tumors, IX: Reactions of mice with primary subcutaneous tumors to injection of a hemorrhage-producing bacterial polysaccharide". Journal of the National Cancer Institute. 4 (5): 461–76. doi:10.1093/jnci/4.5.461.