6. Using a Punnett Square, workout the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus.
In guinea pigs, homozygous female with white coat colour (bb) is cross with the heterozygous male having black coat colour (Bb). The male gamete will produce two types of gametes i.e. B and b while female will produce only one type of gamete which is b. The F1 progeny will show both individuals with black coat colour and white coat colour in a ratio of 1:1. Here, the phenotypic, as well as the genotypic ratio, will be 1:1.
Parents(male/female) Bb bb
Gametes B b b
Crossing Bb : bb
Black coat colour : White coat colour
Genotypic ratio- Bb:bb 1:1
Phenotypic ratio- Black coat colour : white coat colour 1:1