Crossing over at chiasmata exchanges DNA between non-sister chromatids. Random orientation of bivalents and fertilization also create new allele combinations.
Hemophilia is a sex-linked disease that affected some members of royal families in Europe during the 19th and 20th centuries.
The diagram shows the structure of two chromosomes after the first division of meiosis, assuming that there was no crossing over or chiasmata formation.
Draw the same chromosomes to show their structure at the same stage of meiosis if there had been one chiasma between two gene loci.
State the stage of meiosis where chiasmata formation may occur.