CMMB 403 Tutorial Quiz 2 Question and answers correctly solved

CMMB 403 Tutorial Quiz 2 Question and answers correctly solved CMMB 403 Tutorial Quiz 2 What characterizes each abdominal segment of the ventral side of the larva? - correct answer anterior denticles (point posteriorly) and a posterior naked region, side by side Who looked at fly embryo to identify segmentation genes? - correct answer Christiane Nusslein-Volhard and Eric Wieschaus how do we identify genes or genotypes responsible for a particular phenotype? - correct answer knockout or induce a mutation in that gene - treat adults with mutagen to induce independent mutation - cross with WT females to produce heterozygotes with independent mutation - breed independent heterozygotes with WT to produce more heterozygotes with same mutation - breed heterozygotes together = homozygotes and screen mutants for abnormal phenotypes What mutagen can be used to induce mutation in adult flies - correct answer ethyl methanesulfanote (EMS) Results of forward genetic screen that showed hedgehod mutant - correct answer - mutant was smaller - denticle bands replaced with denticle lawn - denticles duplicated in mirror image - naked region in each segment deleted - same number of segments What does the WT denticle pattern of a segment look like? - correct answer anterior portion covered by denticles pointing to the posterior What does the mutant denticle pattern of a segment look like? - correct answer duplicated mirror image on posterior pointing anteriorly = lawn What is an ortholog - correct answer 2 g