Kinesthetically Exploring Chromosomes from Cell Division and Meiosis to Mendelian Genetics

Abstract

Physical models are widely used to help students understand what happens to chromosomes during mitosis and meiosis. They can also be used to explicate the genotype-phenotype map. This laboratory exercise combines both these subjects at a level appropriate for a college-level genetics class. Students first trace the steps of mitosis and oogenesis, with special attention to ploidy and chromosome count. They then use the alleles arrived at by this process to build marshmallow creatures. Finally, they are introduced to more complicated modes of inheritance such as sex-linked traits, incomplete dominance, multiple alleles, and polygenic traits. Evidence of positive student attitudes and learning outcomes is presented.