- Observe a high-tech lab technique in action in this excellent Flash application, whilst learning how cancer cells and healthy cells express genes differently.
- 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
- 20-30 minutes
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)
- 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 excercise individually.
- 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