[Campbell Biology P.474] Based on Figure 20.11 and its accompanying 'Results' section, what ... | Practice Question
Based on Figure 20.11 and its accompanying 'Results' section, what can be concluded about the mRNA expression of the specific Drosophila gene and the characteristics of the amplified product?
A: The mRNA for this gene is expressed from embryonic stages 2 through 6, and the size of the amplified DNA fragment is determined by the distance between the primers used, not the size of the original mRNA.
B: The mRNA is expressed across all six embryonic stages, and the fragment size reflects the exact length of the original mRNA.
C: Expression is limited to stages 1 and 2, and the amplified fragment's size varies depending on the mRNA's size across stages.
D: The presence of a band indicates the exact quantity of mRNA present, and smaller fragments indicate higher expression.
Explanation
The 'Results' section states, 'The mRNA for this gene is expressed from stage 2 through stage 6.' It also clarifies, 'The size of the amplified fragment shown by its position on the gel depends on the distance between the primers that were used not on the size of the mRNA .'