[Campbell Biology P.322] At the molecular level, what is the difference between the dominant... | Practice Question

At the molecular level, what is the difference between the dominant purple-flower allele and the recessive white-flower allele shown in Figure 14.4?

  • A: They are located on different chromosomes.
  • B: The purple-flower allele produces a functional enzyme for pigment synthesis, while the white-flower allele has a DNA sequence that results in a non-functional enzyme.
  • C: The purple-flower allele is made of RNA, while the white-flower allele is made of DNA.
  • D: There is no difference at the molecular level, only in the visible trait.

Explanation

Figure 14.4 illustrates that the DNA sequence of the purple-flower allele leads to the production of an enzyme that synthesizes purple pigment. In contrast, the DNA sequence of the white-flower allele results in the absence of this functional enzyme, leading to white flowers.