In 1909 cytologist Frans Janssens described microscopic chromosomal structures t
ID: 227318 • Letter: I
Question
In 1909 cytologist Frans Janssens described microscopic chromosomal structures that were viewed during prophase I of ___; he called these structures ___ The structures Janssens saw seemed to represent regions in which ___ chromatids of ____ crossed over each other. Thomas Hunt Morgan suggested in 1916 that chiasmata were sites of chromosome breakage and exchange that resulted in ___. In the 1930s publication of studies by Curt Stem in Drosophila and by Harriet Creighton and Barbara McClintock in com showed that recombination is associated with actual ___ between chromosomes. The studies of Stem Creighton and McClintock utilized a combination of ___ that could be viewed in the microscope and ___ controlled by alleles known to reside on the same chromosome. In recombinant organisms ___ indicating that physical exchange had occurredExplanation / Answer
1. Meiosis, Chiasmata
2. Non sister, homologous chromosomes
3. Genetic recombination
4. Physical exchange of parts
5. traits, genetic markers
6. physical markers were inherited with genetic markers