Dr. Reichler╣s Bio 325 TTh 12:30-2pm Print Name:______________KEY_____________
Exam #1 Feb. 19, 2004
Answer each question as succinctly as possible in the space provided. If needed, continue on the back. If you use a drawing as part of your answer, be sure to also include a written explanation. Read each question carefully and don╣t hesitate to ask if a question seems unclear. These questions have specific answers, although for some, more than one answer is possible. To receive full credit you must clearly and fully answer the question being asked. Each question is worth 6 pts, unless otherwise noted, for a total of 103 points possible for this exam.
1. When designing an experiment using the rules of Strong Inference, what is the goal of the experiment? (4 pts)
To disprove one or more hypotheses.
No, complementary sequences within an RNA strand are critical for forming a 3-D structure, and the 3-D structure is critical for RNA having enzymatic activity.
Any one of: One of the voles has an enhancer that increases gene expression while the other does not. One of the voles has a promoter that attracts transcription factors that are more efficient at recruiting RNA polymerase while the other has a less active promoter.
9. How can a mutation cause a cell to lose the ability to perceive an environmental stimulus?
12. A cell responds to a signal by changing a membrane bound protein to a secreted protein. How does the cell do this?
As the protein is being translated on the rough ER, the signal peptide is clipped off thereby releasing the protein into the lumen of the ER, where it will travel through the Golgi to the exterior of the cell.
13. How could you test which part of a protein was the signal peptide that directed that protein to the nucleus?
Remove various parts of the protein and see whether it is still transported to nucleus. OR Add various parts of the protein to some other protein, and see whether the hybrid protein is transported to nucleus.
Any three of: promoter, introns, terminator, non-gene DNA, genes coding for rRNA/tRNA/snRNA.
15. DNA is double stranded, but only one strand is used to make RNA. Why can each RNA polymerase read only one strand of DNA at a time?
RNA synthesis only occurs in a 3╣ direction. Since DNA is anti-parallel, only one of the two strands can be read.
17. Apply rules 1 and 2 of Strong Inference (the parts prior to actually doing any experiments) to answer the following question: What causes diabetes?