Purple petal color in pea plants is dominant to white petal color. two heterozygous pea plants are crossed. what ratio of the offspring will have white petals? : express this in a percentage. %

If both parents are heterozygous for the same trait, it means that both parents have both of the alleles, one for purple petals and one for white petals, so the crossing will lead to an offspring that will present the following genotype proportions:
Purple-colored petals (dominant characteristic, both alleles dominant) - 1/4
Purple-colored petals (dominant characteristic, one allele dominant, one allele recessive) - 2/4
White-colored petals (dominant characteristic, both alleles recessive) - 1/4

The ratio of offspring to have white petals will be 1/4 - 25%.

The ratio of the offspring will have white petals is 1/4. Which means 25%  of the offspring will have white petals.

According To the Mendel's Law:

When two heterogygous parents cross,

Phenotype ratio of offspring with dominant and recessive character  is 3:1.Genotype ratio of WW : Ww : ww is 1:2:1.

Find the attachment for cross.

Hence, we can conclude that the ratio of the offspring will have white petals is 1/4. Which means 25%  of the offspring will have white petals.

To know more about Law of  Dominance, refer to the link:

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