Create a punnent square for Genotype:100% Bb (heterozygous black)
Phenotype:100% black
Punnent square for Genotype: 100% Bb (heterozygous black)
B b
B BB Bb
b Bb bb
Phenotype: 100% black
To create a Punnett square for a genotype of 100% Bb (heterozygous black) and a phenotype of 100% black, we'll consider the dominant gene (B) for black color and the recessive gene (b) for a different color (which we'll assume is non-black).
The Punnett square will have two rows and two columns. Here's how it will look:
B b
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B | BB | Bb |
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b | Bb | bb |
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Since the genotype is 100% Bb, both of the squares in the Punnett square will have "Bb" written in them. This means that all offspring resulting from this mating will have the genotype Bb.
Since the phenotype is 100% black, we can conclude that all offspring will exhibit the black color phenotype.