In mice, the black body coloration A dominates over the brown a. The tail length is controlled by the gene, the dominant allele of which

In mice, the black body coloration A dominates over the brown a. The tail length is controlled by the gene, the dominant allele of which, being in the homozygous state (BB), determines the development of the tail of normal length, and the homozygote for the recessive allele (bb) is lethal (mice die at the embryonic stage of development). If this gene is in a heterozygous state (Bb), then mice have truncated tails. What offspring and in what ratio can be expected from crossing:
1) (women) AaBb x (man) aaBb;
2) a diheterozygous female and a male homozygous for the dominant allele of the gene that provides the development of body color, and heterozygous for the gene that determines the length of the tail;
3) a black short-tailed female and a brown short-tailed male?

1) 1/6 black with normal tails, 1/3 black with short tails, 1/6 brown with normal tails, and 1/3 brown with short tails;
2) 1/3 black with normal tails and 2/3 black with shortened tails;
3) a) if the genotype (females) is AaBb, then in F1 1/6 black with normal tails, 1/3 black with shortened tails, 1/6 brown with normal tails and l / 3 brown with shortened tails;
b) if the genotype (females) is AABb, then in F1 1/3 black with normal tails and 2/3 black with short tails: l / 3 brown with short tails.

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