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 plans to cross a geranium that is heterozygous for red flowers with a geranium that is true-breeding for white
flowers
Which Punnett square best describes this cross?
Rr x rr
Rr Rr
Rr rr
To determine the Punnett square for this cross, we need to first understand the genotypes of the two parent geraniums.
The geranium that is heterozygous for red flowers can be represented as Rr, where R denotes the allele for red flowers and r denotes the allele for white flowers.
The geranium that is true-breeding for white flowers can be represented as rr, where both alleles are for white flowers.
Now, let's create the Punnett square:
R r
-------------
r | Rr Rr
r | Rr Rr
In this Punnett square, the top row represents the possible gametes (sperm) from the first parent (Rr), and the left column represents the gametes (eggs) from the second parent (rr).
By combining the gametes from both parents, we get four possible offspring combinations: two with the genotype Rr (red flower) and two with the genotype rr (white flower).
So, the Punnett square that best describes this cross is:
R r
-------------
r | Rr Rr
r | Rr Rr
Note: Each cell in the Punnett square represents a possible genotype combination for the offspring resulting from the cross. The actual phenotype (observable characteristic) of the offspring will be determined by the expression of the dominant allele (R) for red flowers over the recessive allele (r) for white flowers.
To determine the Punnett square for this cross, we need to first identify the alleles for each parent.
In this case, the geranium that is heterozygous for red flowers has the genotype Rr, where R represents the allele for red flowers and r represents the allele for white flowers.
The geranium that is true-breeding for white flowers has the genotype rr, with both alleles being r.
To set up the Punnett square, we will place the alleles of one parent along the top (row) and the alleles of the other parent along the side (column).
The Punnett square for this cross would be:
R r
---------------
r | Rr rr
In this Punnett square, the possible genotypes resulting from the cross are Rr (heterozygous for red flowers) and rr (true-breeding for white flowers).