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Phenotypic rations

7. In corn plants, a dominant allele "I" inhibits kernel color, while the recessive allele "i" permits color when homozygous. At a different locus, the dominant gene "P" causes purple kernel color, while the homozygous recessive genotype pp causes red kernels. If plants heterozygous at both loci are crossed, what will be the phenotypic ratio of the F1 generation?

8. A short-tailed mutant mouse was discovered. Multiple crosses of this mouse to mice with normal tail length produced 27 long-tailed mice and 25 short-tailed mice. A series of crosses among short tailed mice were made and 21 short-tailed mice and 11 long-tailed mice were produced. Study these results and determine which allele is dominant and explain the ratios observed with regards to the genotypes of the parents in each cross.

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7.The plants crossed are Ii/Pp, and there are 3 phenotypes-purple kernels, red kernels, or colorless kernels.
75% of offspring will be colorless.
75% of the colored ones will be purple (18.75%), while the rest will be red (6.25%)
So the ratio is 12:3:1 colorless:purple:red

8.Because crossing between short-tailed mice ...

Solution Summary

Multiple problems looking at expected phenotypic rations and the related genotypes