A cross of a red (AA) cow with another white (BB) cow results in an F1 breed of rowan (AB) cows. Self-insemination of F1 rowan (AB) cows resulted in 1 red, 2 rowan and 1 white cow in R2.
here,
The gene responsible for red color is A
Genotype AA in red
again,
The gene responsible for white color is B
Genotype BB is white
The first progeny is F1 and the second progeny is F2
Parents : ♂ × ♀
Phenotype: Red and white
Genotype : AA BB
Gamit : (A) (B)
F1 Breed : AB (Rowan)
Self fertilization : F1×F1
Parents : ♂ × ♀
Phenotype: Rowan Rowan
Genotype : AB AB
Gamit : (A) (B) (A) (B)
F2 progeny (checker board)
Comment: It can be seen from the checker board, out of 4 cows, 1 is red, 2 is rowan and 1 is white.
Phenotypic ratio : Red : Rowan : White = 1:2:1