Cross a homozygous dominant individual for brown hair with an individual who is blond hair . remember the starting are the parental generation. What you are getting with results are the offspring ( the F1 generation)

The F1 offsprings will be heterozygous (Bb) with a brown hair phenotype

Explanation:

This is a cross involving a single gene coding for hair color in humans. According to the question, the allele for brown hair (B) is dominant over the allele for blonde hair (b).

The question involves a cross between a homozygous dominant individual (BB) i.e. contains same brown alleles and an individual that has blonde hair, which will be homozygous recessive (bb) since the recessive trait (blonde hair) can only be expressed in a homozygous state. Hence, BB and bb are the Parental or P generation. (See attached image for punnet square).

Parents with genotypes BB and bb will produce F1 offsprings with all having genotype: Bb, which is heterozygous for the dominant trait (brown). Hence, all the F1 offsprings will exhibit a brown hair phenotype since the brown allele (B) will make the phenotypic expression of the blonde allele (b).

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