Define linkage and explain why linkage interferes with independent assortment.

Distinguish between parental and recombinant phenotypes. Explain how crossing over can unlink genes.

Describe sex determination in humans.

Describe the inheritance of a sex-linked gene such as color-blindness.

Explain why a recessive sex-linked gene is always expressed in human males.

Explain how an organism compensates for the fact that some individuals have a double dosage of sex-linked genes while others have only one.

Distinguish between nondisjunction, aneuploidy and polyploidy. Give an example of aneuploidy and polyploidy.

Explain why sex chromosome aneuploidies result in less severe conditions than those from autosomal aneuploidies.

Understand how chromosome breakage results in deletions, duplications, translocations, and inversions. Know the difference between each one.