Question

In pea plants, the allele for red flower color, F, is completely dominant to the allele for white flower color, f. Complete the Punnett square showing the genotypes possible among the offspring when two heterozygous individuals are crossed.

Answer 1

In a cross between two heterozygous pea plants with genotypes Ff for flower color, the offspring's genotypes can be predicted using a Punnett square, resulting in a genotypic ratio of 1 FF: 2 Ff: 1 ff and a phenotypic ratio of 3 red to 1 white.

Step-by-step explanation:

Predicting Offspring Genotypes in Pea Plants

When two heterozygous individuals for flower color in pea plants are crossed, each individual has the genotype Ff (F for red and f for white). A Punnett square is used to predict their offspring's genotypes. Since F is dominant over f, Ff individuals have red flowers. The Punnett square for this cross is:

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• Top row (parental gametes): F f
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• Side column (parental gametes): F f

When you fill in the Punnett square, the genotypes of the possible offspring are:

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• FF (red flowers)
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• Ff (red flowers, since the F allele is dominant)
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• Ff (same as above)
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• ff (white flowers, since there is no dominant allele)

The genotypic ratio is 1 FF: 2 Ff: 1 ff, which translates to a phenotypic ratio of 3 red: 1 white. This is a common example of Mendelian inheritance where one allele is completely dominant over the other.