Crossing a black (BB) guinea pig with another brown (bb) guinea pig results in a black (Bb) guinea pig in the F1 line. Self-crossing of black (Bb) guinea pigs in the F1 progeny resulted in 3 black and 1 brown guinea pig in the F2 progeny.
here,
The gene responsible for black color is B
Hence, the black genotype is BB
again,
Gene responsible for brown color b
Consequently, the brown genotype is bb
The first progeny is F1 and the second progeny is F2
Parents : ♂ × ♀
Phenotype: Black brown
Genotype : BB bb
Gamit : (B) (b)
1st lineage : Bb (black)
Svanishek : F1×F1
Parents : ♂ × ♀
Phenotype: black black
Genotype: Bb Bb
Gamit : (B) (b) (B) (b)
R2 Vamsa (Checker Board)
Remarks: From the checker board, out of four guinea pigs, 3 are black and 1 is brown.
Phenotypic ratio : Black : Brown = 3:1