Extensions to Mendelism

Reading:

Chapter 13 (pp. 245, 247-250)

Terms:

Mendelism
heredity
incomplete dominance
codominance
blood groups
multiple alleles
epistasis
gene interaction
pleiotropy
penetrance
expressivity

Distinguish between codominance and incomplete dominance.

Compare and contrast codominance and incomplete dominance with Mendel's results in pea plants.

If there are more than 2 alleles for a gene within a population, how many alleles will a single individual have?

How does the polygenic effect complicate inheritance of a trait?

Consider how the function of a gene product determines whether an allele is recessive, dominant, codominant etc. Consider the biochemical basis for inheritance of traits.

Distinguish between mutant and wild type allele.

Work problems involving the exceptions to Mendel's results.

What is the basis for differences (at the DNA level) between mutant and wild type alleles?

Be able to answer questions of inheritance regarding traits that are inherited by incomplete dominance, multiple alleles, and codominance.

Describe the biochemical basis for the examples of epistasis given in class.

Distinguish between the epistatic and hypostatic genes.

Describe the concepts of variable expressivity and incomplete penetrance.

What factors contribute to expressivity and penetrance?

Describe some environmental effects on phenotype.