Answer :
To solve this problem, we'll use the information provided by the Punnett square to determine the expected ratio of red-to-white flowering plants in the F2 generation.
1. Understanding Alleles for Flower Color:
- The allele "R" is dominant and results in red flowers. Plants with genotypes "RR" or "Rr" will have red flowers.
- The allele "r" is recessive and results in white flowers. Only plants with the genotype "rr" will have white flowers.
2. Analyzing the Punnett Square:
- The Punnett square given is:
```
| | R | r |
|--- |--- |--- |
| R | RR | Rr |
| R | RR | Rr |
```
- From this square, we can see the possible genetic combinations when crossing the two F1 geraniums (both are "Rr").
3. Determine Possible Outcomes:
- The possible offspring genotypes are:
- "RR" (First row, first column): 2 times
- "Rr" (First row, second column and second row, second column): 2 times
4. Calculate Expected Phenotypes:
- Red Flowers: The plants with genotypes "RR" and "Rr" will have red flowers.
- Total outcomes showing red flowers = 2 (RR) + 2 (Rr) = 4
- White Flowers: Only the genotype "rr" would result in white flowers, but there are no "rr" in the given Punnett square.
5. Expected Phenotypic Ratio:
- Red: 4 parts (since each "RR" contributes 1 and each "Rr" contributes 1)
- White: 0 parts (since there are no "rr" in the Punnett square)
6. Final Interpretation:
- Since all the plants in the F2 generation shown in this Punnett square will have red flowers, the ratio of red to white flowers is all red.
Therefore, when the horticulturalist crosses these F1 generation geraniums, she would expect all of the plants in the F2 generation to have red flowers.
1. Understanding Alleles for Flower Color:
- The allele "R" is dominant and results in red flowers. Plants with genotypes "RR" or "Rr" will have red flowers.
- The allele "r" is recessive and results in white flowers. Only plants with the genotype "rr" will have white flowers.
2. Analyzing the Punnett Square:
- The Punnett square given is:
```
| | R | r |
|--- |--- |--- |
| R | RR | Rr |
| R | RR | Rr |
```
- From this square, we can see the possible genetic combinations when crossing the two F1 geraniums (both are "Rr").
3. Determine Possible Outcomes:
- The possible offspring genotypes are:
- "RR" (First row, first column): 2 times
- "Rr" (First row, second column and second row, second column): 2 times
4. Calculate Expected Phenotypes:
- Red Flowers: The plants with genotypes "RR" and "Rr" will have red flowers.
- Total outcomes showing red flowers = 2 (RR) + 2 (Rr) = 4
- White Flowers: Only the genotype "rr" would result in white flowers, but there are no "rr" in the given Punnett square.
5. Expected Phenotypic Ratio:
- Red: 4 parts (since each "RR" contributes 1 and each "Rr" contributes 1)
- White: 0 parts (since there are no "rr" in the Punnett square)
6. Final Interpretation:
- Since all the plants in the F2 generation shown in this Punnett square will have red flowers, the ratio of red to white flowers is all red.
Therefore, when the horticulturalist crosses these F1 generation geraniums, she would expect all of the plants in the F2 generation to have red flowers.
