Introduction: In 1866 an Austrian monk, Gregor Mendel, presented the results of painstaking experiments on the inheritance patterns of garden peas. Those results were heard, but probably not understood, by Mendel’s audience. Now, more than a century later, Mendel’s work seems elementary to modern–day geneticists, but its importance cannot be overstated. The principles generated by Mendel’s pioneering experimentation are the foundation for genetic counseling so important today to families with health disorders having a genetic basis. It’s also the framework for the modern research that is making inroads in treating diseases previously believed to be incurable. In this era of genetic engineering the incorporation of foreign DNA into chromosomes of unrelated species—it easy to lose sight of the basics of the process that makes it all possible. These were his conclusions: The hereditary determinants are of a particulate nature. These determinants are called genes. Each parent has a gene pair in each cell for each trait studied. The F1 from a cross of two pure lines contains one allele for the dominant phenotype and one for the recessive phenotype. These two alleles comprise the gene pair. One member of the gene pair segregates into a gamete, thus each gamete only carries one member of the gene pair. Gametes unite at random and irrespective of the other gene pairs involved.(Carlson)
The purpose of this lab is to teach students how traits of an organism can be predicted with a dihybrid cross using the recessive and dominant traits. Using a dihybrid cross given the phenotype and genotype of F1 (parents), the traits of offspring should be predictable with ratios derived from the dihybrid cross.
Materials and Methods: Part A- Materials furnished are containers of green and albino seedlings. Count the number of green and albino seedlings, and add total number of seedlings. Then Calculate the ratio of green to albino seedlings.(stallsmith)
Cited: 1. Bruce W. Stallsmith. 2013. Laboratory Manual for Principles of Biology 2nd Edition. Cengage Learning. Mason, OH. 31-32 2. Campbell, Neil A. and Jane Reece. 2002. Biology (6th ed.) Benjamin/Cummings Publ. Co., Redwood City, CA 3. Carlson, Elof Axel. Mendel 's Legacy: The Origin of Classical Genetics. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory, 2004. Print