People to Know - AP Biology Exam Questions and Answers

People to Know - AP Biology Exam Questions and Answers Gregor Mendel Monk who grew up in Austria, experimented with garden peas in 1857 to study inheritance, documented "particulate mechanism", came up with laws of independent assortment and segregation. Thomas Hunt Morgan Came up with first solid evidence associating a specific gene with a specific chromosome by working with various varieties of Drosophila; invented notation for symbolizing alleles; discovered sex-linked trait of white eyes. Watson & Crick American scientists who were the first to discover the structure of DNA as well as come up with a hypothesis for the method of DNA replication (semiconservative model). Frederick Griffith 1928, studied streptococcus pneumoniae; 2 strains of the bacteria that when killed with heat and mixed with nonpathogenic bateria, acquired pathogenicity - discovered phenomenon of transformation. Avery & MacLeod Researched the identity of the Griffith's transforming substance, discovering it to be DNA by ruling out the possibility of RNA and protein. Erwin Chargaff Analyzed base composition of DNA from multiple different organisms; reported that base composition varies from one species to another; provided evidence that DNA is the universal genetic material, also came up with base-pairing rules Rosalind Franklin Colleague of Wilkins and expert X-ray crystallographer, conducted critical experiments resulting in photograph that allowed Watson and Crick to deduce double-helical structure of DNA Maurice Wilkins Worked at King's College in London, helped with research on the discovery of the structure of DNA. Meselson & Stahl Devised experiment to test the three possible models for DNA replication (semiconservative, conservative, dispersive) using nucleotides labeled with nitrogen isotopes. (1950's) Archibald Garrod British physician, first to suggest that genes dictate phenotypes through enzymes that catalyze specific chemical reactions in the cell; disease symptoms reflect an inability to produce a particular enzyme (ex. alkaptonuria)