Chapter 18 | Mendel’s Experiments and Heredity
- Describe one of the reasons why the garden pea was an excellent choice of model system for studying inheritance.
- How would you perform a reciprocal cross for the characteristic of stem height in the garden pea?
- The gene for flower position in pea plants exists as axial or terminal alleles. Given that axial is dominant to terminal, list all of the possible F1 and F2 genotypes and phenotypes from a cross involving parents that are homozygous for each trait. Express genotypes with conventional genetic abbreviations.
- Use a Punnett square to predict the offspring in a cross between a dwarf pea plant (homozygous recessive) and a tall pea plant (heterozygous). What is the phenotypic ratio of the offspring?
- Can a human male be a carrier of red-green color blindness?
- Use the probability method to calculate the genotypes and genotypic proportions of a cross between AABBCc and Aabbcc parents.
- Explain epistatis in terms of its Greek-language roots “standing upon.”
- In Section 12.3, “Laws of Inheritance,” an example of epistasis was given for the summer squash. Cross white WwYy heterozygotes to prove the phenotypic ratio of 12 white:3 yellow:1 green that was given in the text.
- Explain how the Chromosomal Theory of Inheritance helped to advance our understanding of genetics.
- Using diagrams, illustrate how nondisjunction can result in an aneuploid zygote.
