IB Biology Practical Investigations/Genetics/DNA Microarray Virtual Lab

DNA MICROARRAY TEACHING OBJECTIVE: Observe a high-tech lab technique in action in this excellent Flash application, whilst learning how cancer cells and healthy cells express genes differently. TASK OUTCOMES: By the end of this activity, students will be able to: describe the function and origin of the DNA Microarray perform a simple virtual lab to compare the microarrays of healthy cells and cancer cells illustrate how cancer cells express genes differently to healthy cells Explain the function of reverse transcriptase in a biotechnological application TIME REQUIRED: 20-30 minutes INTRODUCTION: In this excellent Flash application from learn.genetics (Utah university), students are introduced to the 'new' science of genomics and are shown how a DNA microarray works. Thay are then instructed to carry out a virtual microarray that illustrates the genetic difference between a healthy skin cell and a melanoma cell. Students can use this task as a means to learn about genomics and the use of reverse transcriptase and to revise protein synthesis. MATERIALS AND EQUIPMENT: DNA Microarray virtual lab from Teacher-set questions OTHER RESOURCES NEEDED: Individual access to computers is beneficial Internet connection Macromedia Flah Player (latest version) INSTRUCTIONS: Send students to the learn.genetics homepage and ask them to find the DNA microarray in the virtual labs section. Students complete the microarray learning exercise individually. SAMPLE QUESTIONS What is the main difference between Genetics and Genomics? (scale of work and time consumption) Which of the following statements are true? An erythrocyte and a skin cell in the same body contain the same DNA. (T) Different genes are expressed in different cell types within the same organism. (T) Gene expression can be observed as production of tRNA. (F - mRNA) Each spot on a Microarray represents one gene. (T) A cancer cell will express most of the same genes as a healthy cell. (T) Reverse transcriptase makes a new strand of RNA. (F - it makes copy DNA (cDNA)) Produce a flow-chart of the process of a microarray If a gene is not expressed, what would you expect to see on a microarray scan? green marker red marker yellow marker no marker (T) IDEAS FOR FURTHER INVESTIGATION learn.genetics has a number of excellent Flash applications and podcasts suitable for DP Biology. SOURCES AND REFERENCES: wikipedia: DNA Microarray learn.genetics at the University of Utah