Answer :
To solve this question, we want to understand how the genetic cross between two geraniums with specific flower colors will work and what their offspring will look like.
1. Understanding the genetics of the flowers:
- The allele for red flowers is represented by 'R'. It is the dominant allele.
- The allele for white flowers is represented by 'r'. It is the recessive allele.
2. Description of the parents:
- A geranium that is true-breeding for red flowers has the genotype 'RR'. This means it has two dominant alleles.
- A geranium that is true-breeding for white flowers has the genotype 'rr'. This means it has two recessive alleles.
3. Producing the offspring:
- When a true-breeding red flower (RR) is crossed with a true-breeding white flower (rr), each parent contributes one allele to the offspring.
- The red flower parent (RR) contributes an 'R' allele, and the white flower parent (rr) contributes an 'r' allele to each offspring.
4. Predicting the genotype of the offspring:
- Every offspring will receive one 'R' allele from the red parent and one 'r' allele from the white parent.
- Therefore, all offspring will have the genotype 'Rr'.
5. Punnett Square for this cross:
- You can visualize this genetic cross using a Punnett square, where:
- The top row and left column represent the alleles from each parent.
- The possible combinations fill in the boxes within the square.
```
| R | R |
--------------
r | Rr | Rr |
--------------
r | Rr | Rr |
```
6. Conclusion:
- All possible combinations result in the genotype 'Rr'.
- Since 'R' is the dominant allele, all the offspring will exhibit red flowers.
Thus, the Punnett square shows that all the geraniums produced from this cross will have the genotype Rr and will have red flowers.
1. Understanding the genetics of the flowers:
- The allele for red flowers is represented by 'R'. It is the dominant allele.
- The allele for white flowers is represented by 'r'. It is the recessive allele.
2. Description of the parents:
- A geranium that is true-breeding for red flowers has the genotype 'RR'. This means it has two dominant alleles.
- A geranium that is true-breeding for white flowers has the genotype 'rr'. This means it has two recessive alleles.
3. Producing the offspring:
- When a true-breeding red flower (RR) is crossed with a true-breeding white flower (rr), each parent contributes one allele to the offspring.
- The red flower parent (RR) contributes an 'R' allele, and the white flower parent (rr) contributes an 'r' allele to each offspring.
4. Predicting the genotype of the offspring:
- Every offspring will receive one 'R' allele from the red parent and one 'r' allele from the white parent.
- Therefore, all offspring will have the genotype 'Rr'.
5. Punnett Square for this cross:
- You can visualize this genetic cross using a Punnett square, where:
- The top row and left column represent the alleles from each parent.
- The possible combinations fill in the boxes within the square.
```
| R | R |
--------------
r | Rr | Rr |
--------------
r | Rr | Rr |
```
6. Conclusion:
- All possible combinations result in the genotype 'Rr'.
- Since 'R' is the dominant allele, all the offspring will exhibit red flowers.
Thus, the Punnett square shows that all the geraniums produced from this cross will have the genotype Rr and will have red flowers.
