Essential Knowledge 3.A.3

The chromosomal basis of inheritance provides an understanding of the pattern of passage (transmission) of genes from parent to offspring.

Rules of probability can be applied to analyze passage of single gene traits from parent to offspring.

Segregation and independent assortment of chromosomes result in genetic variation. Segregation and independent assortment can be applied to genes that are on different chromosomes. Genes that are adjacent and close to each other on the same chromosome tend to move as a unit; the probability that they will segregate as a unit is a function of the distance between them. The pattern of inheritance (monohybrid, dihybrid, sex-linked, and genes linked on the same homologous chromosome) can often be predicted from data that gives the parent genotype/phenotype and/or the offspring phenotypes/genotypes.

Certain human genetic disorders can be attributed to the inheritance of single gene traits or specific chromosomal changes, such as nondisjunction. Examples of human genetic disorders include sickle cell anemia, Tay-Sachs disease, Huntington’s disease, X-linked color blindness, Trisomy 21/Down syndrome, and Klinefelter’s syndrome

Many ethical, social and medical issues surround human genetic disorders. Examples include reproduction issues and civic issues such as ownership of genetic information, privacy, historical contexts, etc.

Students should be able to:

LO 3.12 Construct a representation that connects the process of meiosis to the passage of traits from parent to offspring.

LO 3.13 Pose questions about ethical, social or medical issues surrounding human genetic disorders.

LO 3.14 Apply mathematical routines to determine Mendelian patterns of inheritance provided by data sets.