In peas, yellow seeds (Y) are dominant over green seeds (y). If a yy plant is crossed with a YY plant, what ratio of plants in the offspring would you predict?

The ratio of yellow seed phenotype with green seed color seed offsprings will be 4:0.

Explanation:

Given that:

Dominant trait is Y (yellow seed color)

recessive trait is y (green seeds color)

cross between YY and yy, According Mendelian Genetics dominant trait will be seen in phenotype as it masks the effect of recessive gene.

Punnet square shows that:

    Y      Y

y   Yy    Yy

y   Yy     Yy

All the plants produced will be tall phenotype.

The yellow seed plant plants will be heterozygous i.e Yy

the phenotype ratio is 4:0

The genotype ratio is 4:0

The genotype of the offspring is Yy

phenotype is yellow colored seed plant.

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