If pure bred-flowered pea plant(PP) pollinates with a purebred white-flowered pea plant(pp), what is the probability the the flower color of their offspring will be purple? White?
X / PP / Pp
PP / pp / pP
Pp / pP / PP
Here is the punette square
All would be Pp. What does that tell you?
To determine the probability of the flower color of the offspring, we need to consider the genetic makeup of the parent plants. In this scenario, the purebred flowered pea plant (PP) is homozygous dominant for purple flowers, while the purebred white-flowered pea plant (pp) is homozygous recessive for white flowers.
When these two plants cross-pollinate, the resulting offspring will have a genotype of Pp, with one dominant allele for purple flowers and one recessive allele for white flowers.
The color purple is a result of the dominant allele (P), and therefore, any offspring with at least one P allele will have purple flowers. On the other hand, the color white is a result of the recessive allele (p), so only the offspring with two copies of the recessive allele (pp) will have white flowers.
To calculate the probability of each flower color, we can use Punnett squares or specific genetic ratios.
Probability of offspring with purple flowers (Pp):
There are two possibilities for the genetic makeup of the offspring: PP and Pp. Since the Purebred flowered pea plant (PP) has only 1 possibility, the probability of getting offspring with purple flowers is 100% or 1.
Probability of offspring with white flowers (pp):
Since the Purebred white-flowered pea plant (pp) has only one possibility pp, the probability of getting offspring with white flowers is also 100% or 1.
So, the probability of offspring having purple flowers is 100% (1), and the probability of offspring having white flowers is also 100% (1).
To determine the probability of the flower color of the offspring resulting from the cross between a purebred flowered pea plant (PP) and a purebred white-flowered pea plant (pp), we need to understand the inheritance pattern of the color trait in pea plants.
In pea plants, flower color is determined by a single gene with two alleles: the dominant allele (P) for purple flower color and the recessive allele (p) for white flower color. The dominant allele (P) masks the expression of the recessive allele (p).
So, when a purebred flowered pea plant (PP) pollinates a purebred white-flowered pea plant (pp), all the offspring will inherit a single copy of the dominant allele (P) from the purple-flowered parent and a single copy of the recessive allele (p) from the white-flowered parent. This results in all the offspring having the genotype Pp.
The genotype Pp represents heterozygosity, where the dominant allele (P) expresses purple flower color, and the recessive allele (p) does not express the color, resulting in the offspring having purple flowers. Therefore, the probability of the offspring having purple flowers is 100%.
Since all the offspring have the genotype Pp, none of them will inherit two copies of the recessive allele (pp) for white flower color. So, the probability of the offspring having white flowers in this specific cross is 0%.
To summarize:
- Probability of offspring having purple flowers: 100%
- Probability of offspring having white flowers: 0%