Question 1
Thalassemias are primarily caused by:
◦ base substitutions that alter α or β globin genes.
◦ deletions that eliminate α or β globin genes.
◦ base substitutions that alter γ or δ globin genes.
◦ deletions that eliminate γ or δ globin genes.
◦ insertions that alter α or β globin genes.
Question 2
The crossover fixation model predicts that:
◦ any sequence of DNA that is not under selective pressure will be taken over by a series of identical tandem repeats.
◦ any sequence of DNA that is under selective pressure will be taken over by a series of identical tandem repeats.
◦ any sequence of DNA that is not under selective pressure will be taken over by a series of nonidentical tandem repeats.
◦ any sequence of DNA that is under selective pressure will be taken over by a series of nonidentical tandem repeats.
◦ any sequence of DNA that is not under selective pressure will gradually reduce its frequency of crossing over.
A hypothetical model of the process of cell-wall expansion.
Lambda phage inserts by a crossover at a specific site
Mode lof Chromosome Crossover
Single-cell circulation model
Trombone Model of DNA
Three-dimensional model of DNA.