4. If one strand of DNA has the sequence of nitrogenous bases AACTG, its complementary strand has the sequence . A. TTGAC
B. AACTG
C. UUBAC
D. AACUC

11. What is a mutagen?

A. a type of base pair mutation
B. the cellular response to a detected mutation
C. any type of protein mutation
D. anything that causes a DNA mutation

12. Which of the following is NOT an example of a mutation?

A. the removal of a base pair
B. the copying of a base pair
C. the replacement of a base pair
D. the addition of a base pair