In pea plants, purple flower color is dominant to white, and tall height is domi
ID: 279341 • Letter: I
Question
In pea plants, purple flower color is dominant to white, and tall height is dominant to dwarf. The genes controlling flower color and height are on separate chromosomes. Which of the following satisfies the expected distribution of phenotypes from a cross of two pea plants that are both heterozygous for both flower color and plant height?
B. 63 purple-flowered, tall plants; 28 purple-flowered, dwarf plants; 27 white-flowered, tall plants; 7 white-flowered, dwarf plants.
C. 132 purple-flowered, tall plants; 138 white-flowered, dwarf plants.
D. 27 purple-flowered, tall plants; 28 purple-flowered, dwarf plants; 31 white-flowered, tall plants; 29 white-flowered, dwarf plants.
E. All purple-flowered, tall plants.
In pea plants, purple flower color is dominant to white, and tall height is dominant to dwarf. The genes controlling flower color and height are on separate chromosomes. Which of the following satisfies the expected distribution of phenotypes from a cross of two pea plants that are both heterozygous for both flower color and plant height?
A. 54 purple-flowered, tall plants; 6 white-flowered, dwarf plants.B. 63 purple-flowered, tall plants; 28 purple-flowered, dwarf plants; 27 white-flowered, tall plants; 7 white-flowered, dwarf plants.
C. 132 purple-flowered, tall plants; 138 white-flowered, dwarf plants.
D. 27 purple-flowered, tall plants; 28 purple-flowered, dwarf plants; 31 white-flowered, tall plants; 29 white-flowered, dwarf plants.
E. All purple-flowered, tall plants.
.Explanation / Answer
Ans : B) 63 purple flowered, tall plants ; 28 purple-flowered , dwarf plants ; 27 white-flowered, tall plants ; 7 white-flowered,dwarf plants.
Since both the parents are heterozygous and it is a dihybrid cross , the phenotypic ratio observed is 9 : 3 : 3 :1.
This is in accordance with the distribution of pehnotypes mentioned in the option B , so it is the correct choice.