Answer :
The correct answer is D. 3 red: 1 white.
To determine the expected ratio of red-to-white flowering geraniums in the F2 generation, we need to analyze the information given about the flower color inheritance and the results from the Punnett square.
In this scenario, the traits for flower color are determined by the following alleles:
Red flowers: Dominant allele (R)
White flowers: Recessive allele (r)
The genotypes for flower color are as follows:
RR: Homozygous dominant (red flowers)
Rr: Heterozygous (red flowers)
rr: Homozygous recessive (white flowers)
Step-by-step Breakdown:
Crossing the F1 Generation: The horticulturist is crossing two individuals from the F1 generation, which are both heterozygous for the trait (Rr).Creating the Punnett Square:Each parent (Rr) can contribute either an R or an r allele.The Punnett square looks like this:Analyzing the Results: The offspring genotypes from this cross are:1 RR (red)2 Rr (both red)1 rr (white)So, when combining these, we can summarize the phenotypes:Total red flowers: 1 (RR) + 2 (Rr) = 3Total white flowers: 1 (rr)
Expected Ratio:
Thus, the expected phenotype ratio of red to white flowering plants is:
[tex]\text{Ratio of red to white: } 3:1[/tex]
Conclusion:
From the options given:
- A. 2 red: 2 white
- B. 1 red: 3 white
- C. all red
- D. 3 red: 1 white
the question table is attached below
To determine the expected ratio of red-to-white flowering plants in the F2 generation, we can analyze the given Punnett square.
The given cross is between two geraniums from the F1 generation, which have both inherited one red allele (R) and one white allele (r). We observe the following combinations in the Punnett square:
1. RR (red flowers)
2. Rr (red flowers)
3. Rr (red flowers)
4. rr (white flowers)
Step-by-Step Analysis:
1. Identify Red Flower Combinations:
- Red flowers appear when the plant has at least one dominant R allele. This includes the combinations RR and Rr.
- Based on the Punnett square, these are found three times: once in the RR square and twice in the Rr squares.
2. Identify White Flower Combinations:
- White flowers occur only when the plant has two recessive r alleles, which is the rr combination found in the last square.
- This configuration appears once.
3. Calculate the Phenotypic Ratio:
- Count the number of red flower combinations: 3 (one RR and two Rr).
- Count the number of white flower combinations: 1 (one rr).
- Thus, the ratio of red-to-white flowering plants is 3:1.
Therefore, in the F2 generation, we expect to see a phenotypic ratio of 3 red flowering plants to 1 white flowering plant.
The given cross is between two geraniums from the F1 generation, which have both inherited one red allele (R) and one white allele (r). We observe the following combinations in the Punnett square:
1. RR (red flowers)
2. Rr (red flowers)
3. Rr (red flowers)
4. rr (white flowers)
Step-by-Step Analysis:
1. Identify Red Flower Combinations:
- Red flowers appear when the plant has at least one dominant R allele. This includes the combinations RR and Rr.
- Based on the Punnett square, these are found three times: once in the RR square and twice in the Rr squares.
2. Identify White Flower Combinations:
- White flowers occur only when the plant has two recessive r alleles, which is the rr combination found in the last square.
- This configuration appears once.
3. Calculate the Phenotypic Ratio:
- Count the number of red flower combinations: 3 (one RR and two Rr).
- Count the number of white flower combinations: 1 (one rr).
- Thus, the ratio of red-to-white flowering plants is 3:1.
Therefore, in the F2 generation, we expect to see a phenotypic ratio of 3 red flowering plants to 1 white flowering plant.
