Question

34. Two black female mice are crossed with a brown male. Later female 1
produced 9 black and 7 brown offsprings, female II produced 57 black off
springs during 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

Answer:

male genotype :bb

female 1 genotype : Bb

female 2 genotype :BB

Where B stands for dominant allele causing black color

and b stands for recessive allele responsible for brown color

Explanation:

since 1st cross gave two phenotypes then both parents must be heterozygous

and cross 2 gave all black so we can tell the genotype of female2 is homozygous dominant (BB)