Which is correct genotypic rotio of mendal dihibrid cross among 1:2:1:2:4:2:1:2:1 and 1:2:2:4:1:2:1:2:1 ?
1 Answer
1:2:2:4:1:2:1:2:1 is the correct genotypic ratio of Mendel's Dihybrid cross
Explanation:
Mendel's dihybrid phenotypic ratio is 9:3:3;:1.
Lets us explain by taking the example of pea plant .
A cross is made between a pure pea plant with yellow colored cotyledons and round seeds with pure pea plant with green colored cotyledons and wrinkled seeds.
Yellow color of cotyledons(Y) is dominant over green color (y).
Round shape of seed (R) is dominant over wrinkled seeds (r).
All the plants in
We get
Yellow round pea plants (9) will have 4 types of genotypes:
YYRR (1), YYRr (2), Yy RR (2) and YyRr (4).
Yellow wrinkled (3) will have 2 genotypes:
YYrr (1), Yyrr (2).
Green round (3) will have 2 genotypes:
yyRR (1), yyRr (2)
Green wrinkled (1) will have only one genotype:
yyrr(1).
Thus the F2 dihybrid genotypic ratio will be 1:2:2:4:1:2:1:2:1