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.
a. Rules of probability can be applied to analyze passage of single gene traits from parent to offspring.
b. Segregation and independent assortment of chromosomes result in genetic variation.
Evidence of student learning is a demonstrated understanding of each of the following:
1. 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.
3. 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.
Many ethical, social and medical issues surround human genetic disorders.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Reproduction issues
• Civic issues such as ownership of genetic information, privacy, historical contexts, etc.
Essential knowledge 3.A.4: The inheritance pattern of many traits cannot be explained by simple Mendelian genetics.
a. Many traits are the product of multiple genes and/or physiological
Evidence of student learning is a demonstrated understanding of the
1. Patterns of inheritance of many traits do not follow ratios
predicted by Mendel’s laws and can be identified by quantitative
analysis, where observed phenotypic ratios statistically differ
from the predicted ratios.