DNA-Genes Transcription and Mutations

Pre Lab Questions:

1.  Which protein transcribes DNA?

2.  Where is DNA transcribed?

3.  What is the region of DNA called where transcription begins?

4.  What is the product of translation?

5.  What is the start codon sequence found in mRNA?

Click on the link below to access the online lab.

http://auth.mhhe.com/biosci/genbio/virtual_labs_2K8/pages/DNA_And_Genes.html

Download and print the instructions for reference as you work through the lab.  As you work through the lab fill in the table below.  Use this information to answer the questions that follow contained in this document.

First read through the mutation guide.  Once you close the guide you will see the buttons to begin the simulation.  Note, you will be translating the mRNA strand into a protein.  As you work through each of the mutations fill in the charts below.  You must complete at least 3 mutations for this lab activity.  It’s good practice working with the codon table .

– Aris labs calls the codon table the ‘Genetic Code Chart’.  Use the amino acid abbreviation for the protein sequence.  For example the amino acid proline is abbreviated as pro.

You have to fill in all the letters AND the resulting amino acid sequence by dragging and dropping before you click the [check] button.

6. “Mutation Rule” states:  ___________________________________________

7. “Mutation Rule” states:  ___________________________________________

8. “Mutation Rule” states:  ___________________________________________

Post Lab Questions

9.  Explain the difference between a missense, nonsense and silent mutation.

10.  Explain what a frame shift mutation is and why they are so dangerous.

11.  At what level are mutations introduced – DNA or RNA?

12.  Are all mutations bad?  Explain your answer.