As of September 30, 2005, the North Central Regional Technology in Education Consortium is no longer in operation.
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For most students, the concepts of genes being a part of chromosomes that move from generation to generation in a very organized way can be abstract and confusing. This activity, however, grabs students' interest by focusing on their own characteristics. It allows them to work with their actual traits as they follow them through these abstract processes. Before participating in this lesson, students should be able to use their knowledge of cell structure to locate the genes and chromosomes in the cell. They should also be able to use their understanding of mitosis or cell division to explain why it is necessary to have a second cell division (meiosis) for the production of the sex cells so that healthy offspring can be produced after receiving genetic information from both parents. (See "Virtual Meiosis," http://www.biology.uc.edu/vgenetic/meiosis/prophase1.htm) The students should also be familiar with vocabulary such as dominant or recessive traits, genotype, phenotype, homozygous, heterozygous, and allele.
Unfortunately, students often develop the misconception that chromosomes are always double, as they appear in metaphase spreads and karyotypes. As the students follow each pair of chromosomes through meiosis, they will see that the second division returns them to single chromosomes with a single copy of the genes. Often students fail to realize that there are many genes on each chromosome and that to produce a normal child, they must get a specific amount and type of genetic material from each parent. After locating their own genes on their chromosomes and following them to their imaginary child, students should realize how these genes get from generation to generation and that a recombination of genes can produce a new phenotype without the loss of that trait for future generations.
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