Lab Description: Students simulate random chromosome selection of a sex linked trait (human baldness) by using coins. The mother is a carrier and the father does not have the recessive gene.
Materials needed: Coins, masking tape, this worksheet.
Lab set up: Students can make their own coins with masking tape or coins can be pre-made and and reused for future classes.
Student knowledge: Dominant and recessive genes, genotype and phenotype expression, carriers of sex linked recessive disorders, expected vs. observed results
Lab Data: 40 trials are recorded on the lab sheet. All lab data can be combined (chart in class or google form/sheet) to help student understanding of expected vs. observed results. "The more trials performed, the closer the observed results will be to the expected results."
Extension: A sex linked pedigree is offered as an extension question at the end of the lab. Instructions are provided to identify male/female and individuals with the tracked trait. No instructions or answer key is provided for solving the pedigree.