Question

4. Two black female mice are crossed with a brown male later female I produced 9 black and 7 brown offsprings female I I produced 57 black offsprings during the first filial generation then
I) what inference can you make concerning inheritance of black and brown coloured mice?
ii) with the help of phenotype given find out what are the genotypes of parents?​

Answer 1

i) Inference regarding the inheritance of black and brown colour. Since the black colour genes are dominant over brown .colour genes, only black coloured offsprings appear in the first filial generation.
(ii) Since both black and brown offsprings are obtained when female 1 is crossed with a brown male (bb), its genotype would be Bb (heterozygous). Female 2 will have genotype BB (homozygous).