A horticulturalist wants to produce geraniums with specific characteristics. She knows that the trait of red flowers is governed by the allele R (RR and Rr), and the trait of white flowers is governed by the allele r (rr).

The horticulturalist crosses two geraniums from the F1 generation. Look at the Punnett square to see this cross.

[tex]\[
\begin{array}{|c|c|c|}
\hline
& R & r \\
\hline
R & R R & R r \\
\hline
r & R r & r r \\
\hline
\end{array}
\][/tex]

Which ratio of red-to-white flowering plants would she expect to see in the phenotypes of the F2 generation?

A. 3 red: 1 white
B. all red
C. 1 red: 3 white
D. 2 red: 2 white

To solve this problem, we'll look at the given Punnett square, which represents the genetic cross of two geraniums from the F1 generation. Here's a breakdown of the genotypes in the Punnett square:

1. RR - This genotype will result in red flowers.
2. Rr - This genotype will also result in red flowers. There are two occurrences of this genotype in the Punnett square.
3. rr - This genotype will result in white flowers.

Now, let's count the occurrences of each phenotype based on the genotypes:

- Red-flowering plants: There are three genotypes that result in red flowers (RR, Rr, and Rr). So, we have a total of 3 red-flowering plants.
- White-flowering plants: There is one genotype that results in white flowers (rr). So, we have 1 white-flowering plant.

Therefore, the expected ratio of red-to-white flowering plants in the F2 generation is 3:1. This means for every 4 plants, 3 will have red flowers, and 1 will have white flowers.