Theory of Evolution
This kit guides students through the thought processes involved in a laboratory-based scientific investigation. Students are asked: Can molecular evidence support the theory of evolution? Why or why not? What explanations can you suggest?
Changes in proteins can reflect changes in the gene pool. Actin and myosin are the major muscle proteins essential for locomotion and survival in all animals. Muscle consists mainly of actin and myosin, but numerous other proteins also comprise muscle tissue. The structures and functions of actin and myosin have remained relatively stable or "conserved" in all animals over evolutionary time. However, other muscle proteins exhibit considerable variation even among closely related species. Detectable variations between organisms' protein profiles reflect physiological adaptations to different environments, but they originate as random DNA mutations. Such mutation events, if favorable, persist through the natural selection process and contribute to the evolution of species — with new specialized functions.
Mutation > Variation > Specialization > Speciation = Evolution
This is an open-ended inquiry-based kit. Students make predictions about their results in prelab activities using internet databases and published phylogenetic information. They generate novel results and apply their findings directly to the problem of solving evolutionary relationships by constructing cladograms (phylogenetic trees). From their gel data, they build up a tree and assign each organism a branch. Students can decide whether their results support their predictions.
Protein Profiler Gel
