Final answer:
Using a Punnett square for a cross between two heterozygous (Hh) corn plants, we can predict a genotypic ratio of 1 HH:2 Hh:1 hh and a phenotypic ratio of 3 tall to 1 short, which aligns with Mendelian laws of inheritance.
Step-by-step explanation:
In a hybrid (heterozygous) cross of corn plants, where normal height (H) is dominant over short height (h), we expect to see a mix of phenotypes in the offspring. If we represent the heterozygous tall plant as Hh, a cross between two Hh plants (Hh x Hh) can be visualized using a Punnett square. The Punnett square has four squares, each representing a possible genotype of the offspring.
We place the alleles from one parent across the top (H and h) and the alleles from the other parent along the side (H and h). After filling in the squares with possible allele combinations from each parent, we can observe the genotypic ratio and the phenotypic ratio of the offspring. In this case, the genotypic ratio for the offspring is:
- 1 HH (homozygous dominant for tall)
- 2 Hh (heterozygous, still tall)
- 1 hh (homozygous recessive for short)
The corresponding phenotypic ratio is 3 tall plants to 1 short plant, which is consistent with the predictions made according to Mendelian principles.