History of genetics of the fruit fly "Drosophila melanogaster". In 1928, Frederick Griffith showed that genes could be transferred. In what is now known as Griffith's experiment, injections into a mouse of a deadly strain of bacteria that had been heat-killed transferred genetic information to a safe strain of the same bacteria, killing the mouse. A series of subsequent discoveries led to the realization decades later that the genetic material is made of DNA (deoxyribonucleic acid). In 1941, George Wells Beadle and Edward Lawrie Tatum showed that mutations in genes caused errors in specific steps in metabolic pathways. This showed that specific genes
3-Methylbutanoic acid 3-Methylbutanoic acid 3-Methylbutanoic acid, also known as β-methylbutyric acid or more commonly isovaleric acid, is an organic compound with the formula (CH)CHCHCOH. It is sometimes classified as a fatty acid. It is a colourless liquid that is sparingly soluble in water, but highly soluble in most common organic solvents. The compound occurs naturally, including in essential oils. Isovaleric acid has a strong pungent cheesy or sweaty smell, but its volatile esters have pleasing scents and are used widely in perfumery. It has been proposed that it is the anticonvulsant agent in valerian. It is a major component of the cause