Question

A researcher creates random copolymers of three nucleotides by mixing polynucleotide phosphorylase with guanine and adenine nucleotides in a ratio of 5 guanine nucleotides to 1 adenine. Which of the following three nucleotide copolymers would most likely be most abundant? A. GGG D. GAA E. AAA B. GAG C. AGA

Answer 1

The answer is A. GGG.

To calculate this, a multiplication rule is used. The multiplication rule calculates the probability that both of two events will occur. In this method, the possibilities of each event are multiplied.

If a ratio is 5 guanine to 1 adenine, this means that the possibility of adenine to be created is $\frac{1}{6}$, and the possibility of guanine to be created is $\frac{5}{6}$.

Now, we will use the multiplication rule to calculate the possibility of creation each of these 5 copolymers:
GGG - $\frac{5}{6}$ × $\frac{5}{6}$ × $\frac{5}{6}$ = 0.58
GAA - $\frac{5}{6}$  × $\frac{1}{6}$ × $\frac{1}{6}$ = 0.02
AAA - $\frac{1}{6}$  × $\frac{1}{6}$ × $\frac{1}{6}$ = 0.005
GAG - $\frac{5}{6}$  × $\frac{1}{6}$ × $\frac{5}{6}$ = 0.12
AGA - $\frac{1}{6}$  × $\frac{5}{6}$ × $\frac{1}{6}$ = 0.02

According to this, the greatest possibility to be created has copolymer GGG.