Answer :
To solve the problem of determining the Punnett square for crossing a true-breeding red-flowered geranium with a true-breeding white-flowered geranium, follow these steps:
1. Identify Parent Genotypes:
- The red-flowered geranium is true-breeding, meaning it has two dominant alleles. Its genotype is [tex]\( RR \)[/tex].
- The white-flowered geranium is also true-breeding, but with two recessive alleles. Its genotype is [tex]\( rr \)[/tex].
2. Set Up the Punnett Square:
- A Punnett square is a grid that shows all possible combinations of alleles from the parents.
- You place the alleles from one parent along the top and the alleles from the other parent along the side.
3. Fill in the Punnett Square:
- Cross each allele from the red-flowered parent (on the top) with each allele from the white-flowered parent (on the side).
- Since the red-flowered parent is [tex]\( RR \)[/tex], both alleles you list across the top of the Punnett square will be [tex]\( R \)[/tex].
- Since the white-flowered parent is [tex]\( rr \)[/tex], both alleles you list down the side of the Punnett square will be [tex]\( r \)[/tex].
4. Determine Offspring Genotypes:
- Fill in each box of the Punnett square by combining the alleles from the top and side of the grid.
- In this case, every box in the Punnett square will be filled with [tex]\( Rr \)[/tex] as each offspring receives one allele [tex]\( R \)[/tex] from the red-flowered parent and one allele [tex]\( r \)[/tex] from the white-flowered parent.
5. Outcome:
- All offspring will have the genotype [tex]\( Rr \)[/tex]. This means all offspring will exhibit red flowers (since the [tex]\( R \)[/tex] allele for red is dominant).
Using the details above, you can match the Punnett square and conclude the correct answer would illustrate a grid where each possibility for the offspring’s genotype is [tex]\( Rr \)[/tex]. This matches none of the examples typically given in options A, B, etc., but the conceptual understanding is critical.
1. Identify Parent Genotypes:
- The red-flowered geranium is true-breeding, meaning it has two dominant alleles. Its genotype is [tex]\( RR \)[/tex].
- The white-flowered geranium is also true-breeding, but with two recessive alleles. Its genotype is [tex]\( rr \)[/tex].
2. Set Up the Punnett Square:
- A Punnett square is a grid that shows all possible combinations of alleles from the parents.
- You place the alleles from one parent along the top and the alleles from the other parent along the side.
3. Fill in the Punnett Square:
- Cross each allele from the red-flowered parent (on the top) with each allele from the white-flowered parent (on the side).
- Since the red-flowered parent is [tex]\( RR \)[/tex], both alleles you list across the top of the Punnett square will be [tex]\( R \)[/tex].
- Since the white-flowered parent is [tex]\( rr \)[/tex], both alleles you list down the side of the Punnett square will be [tex]\( r \)[/tex].
4. Determine Offspring Genotypes:
- Fill in each box of the Punnett square by combining the alleles from the top and side of the grid.
- In this case, every box in the Punnett square will be filled with [tex]\( Rr \)[/tex] as each offspring receives one allele [tex]\( R \)[/tex] from the red-flowered parent and one allele [tex]\( r \)[/tex] from the white-flowered parent.
5. Outcome:
- All offspring will have the genotype [tex]\( Rr \)[/tex]. This means all offspring will exhibit red flowers (since the [tex]\( R \)[/tex] allele for red is dominant).
Using the details above, you can match the Punnett square and conclude the correct answer would illustrate a grid where each possibility for the offspring’s genotype is [tex]\( Rr \)[/tex]. This matches none of the examples typically given in options A, B, etc., but the conceptual understanding is critical.
