This biologist discovered the nucleolar-organizing region in an early experiment, and in a more famous
 experiment characterized the behavior of the Ac and Ds elements.
This scientist identified the first ring chromosome, and also noticed that its structure would be lost at
 meiosis. Along with Blumenschein and Kato, this scientist published a landmark evolutionary study on
 their favorite model organism, and this scientist also characterized the suppressor-mutator or SPM element.
 This biologist discovered the nucleolar-organizing region in an early experiment, and in a more famous
 experiment characterized the behavior of the Ac and Ds elements. This biologist noted that changes in
 aleurone color from generation to generation could be explained by genomic mutability, but her work was
 met with much skepticism. For 10 points, name this biologist who used Zea mays to discover transposons.
This scientist identified the first ring chromosome, and also noticed that its structure would be lost at
 meiosis.
Barbara {McClintock}