Inversion heterokaryotypes are often characterized as having reduced crossing over and reduced fertility.Assume that you were examining a strain of organisms you knew to be inversion heterokaryotypes and saw a relatively high number of double chromatid bridges extending between anaphase I nuclei,as indicated in the following drawing.What is the product of this type of inversion loop?
A)two acentric fragments and two dicentric chromosomes
B)two chromosomes with deletions and two acentric fragments
C)one acentric fragment,one dicentric chromosome,and two wild- type chromosomes
D)two chromosomes with deletions and two with duplications
E)four wild- type chromosomes

Question

Inversion heterokaryotypes are often characterized as having reduced crossing over and reduced fertility.Assume that you were examining a strain of organisms you knew to be inversion heterokaryotypes and saw a relatively high number of double chromatid bridges extending between anaphase I nuclei,as indicated in the following drawing.What is the product of this type of inversion loop? 
A)two acentric fragments and two dicentric chromosomes 
B)two chromosomes with deletions and two acentric fragments 
C)one acentric fragment,one dicentric chromosome,and two wild- type chromosomes 
D)two chromosomes with deletions and two with duplications 
E)four wild- type chromosomes

Quizplus · Accepted Answer

Double chromatid bridges between anaphase I nuclei suggest that there is a failure of homologous chromosomes to properly separate during meiosis. In inversion heterokaryotypes, this is often due to the presence of inversion loops, which result in the formation of dicentric bridges and acentric fragments. Therefore, the product of this type of inversion loop would be two acentric fragments and two dicentric chromosomes.

Inversion Heterokaryotypes Are Often Characterized as Having Reduced Crossing Over