Download Unit 5 quesitons

Unit 5 questions for review
AP biology
The following chapters will be covered: Chapter 14, 15, 17, 18, 19, 33
1. Describe the experiment of Fred Griffith.
2. What was added by the work of Avery, McCarty, and MacLeod?
3. Describe the work of Hershey and Chase. What did this add to our understanding of the
genetic material?
4. Describe the discovery made by Chargaff and state its significance.
5. Describe the model proposed by Watson and Crick (with help from Franklin)
6. How are the deoxyribose sugars joined together into a chain?
7. State the difference between a purine base and a pyrimidine base.
8. Why do the purine and pyrimidine bases always pair together?
9. How are the two strands held together into the double helix?
10. Describe the Meselsohn-Stahl experiment.
11. What did this experiment prove?
12. What is the origin of replication?
13. Describe the replication fork.
14. What enzyme catalyzes DNA replication? What is the source of energy?
15. Describe the reaction that is performed by this enzyme.
16. DNA replication proceeds along both strands in both directions from the origin. How is the
problem of the antiparallel strands solved?
17. Why is primase required in DNA replication?
18. What are Okazaki fragments?
19. How are the spaces between fragments filled?
20. Explain how DNA proofreading and repair occurs.
21. What did Frederick Sanger do?
22. State the purpose of transcription. Briefly describe the process.
23. Why must the genetic code be written in triplets of nucleotides?
24. How many codons does this code allow?
25. Describe the relationship between a DNA triplet, a codon, and an anticodon.
26. What is the evolutionary significance of the genetic code?
27. Describe the role played by promoters and transcription factors in transcription.
28. How is the elongation of the new strand accomplished?
29. State the purpose of translation. Briefly describe the process.
30. How are tRNAs hooked up with the correct amino acid?
31. Describe the structure of a ribosome.
32. During translation, how is the reading frame established?
33. Explain the initiation step in protein synthesis. Include all the steps.
34. Describe elongation. Include all steps.
35. Describe the way in which the end of translation is signaled.
36. Explain what happens to eukaryotic mRNA during its post-transcriptional modification.
Include an explanation of introns and exons. Also include the purpose of both the 5' cap
and the poly-A tail.
37. What purpose is served by signal sequences?
38. Name and describe the different point mutations.
39. What are restriction enzymes and what natural purpose do they serve?
40. What is a vector? Name two common vectors that are used in DNA technology.
41. Briefly outline the steps involved in using bacteria and plasmids to clone a gene.
42. How is cDNA made and why is it sometimes necessary?
43. How can a probe be used to locate a gene of interest once it has been cloned?
44. Explain how gel electrophoresis can be used to separate and visualize DNA fragments.
45. Describe the Sanger method for sequencing DNA.
46. Describe the polymerase chain reaction.
47. Describe the technique of Southern blotting.
48. How are these techniques useful?
49. How can restriction fragment length polymorphisms be used as genetic markers?
50. Briefly explain how DNA technology can used in each of the following areas:
a) diagnosis of disease
b) gene therapy
c) vaccines and pharmaceuticals
d) forensics
f) environmental applications
g) agricultural uses
51. Briefly discuss some ethical and safety concerns surrounding the use of DNA technology.
52. What is a stem cell and why is it important?
53. Briefly describe the levels of DNA packing in eukaryotic cells.
54. What are histones?
55. Describe a possible use for repetitive sequences.
56. Describe and give an example of a multigene family.
57. Draw a diagram of a typical eukaryotic gene and describe the function of each of the
following: enhancer, promoter, exon, intron, cap site, poly-A site, leader, trailer.
58. How can the life of a mRNA be extended? Why would a cell do this?
59. What is gene amplification? When would this technique be used by a cell?
60. Explain the purpose of DNA methylation.
61. Explain the role of oncogenes and tumor-suppressor genes in the development of cancer.
62. What is a homeotic gene?
63. What forms can a viral genome take?
64. Distinguish between a capsid and an envelope.
65. What is meant by host range?
66. Describe the lytic and lysogenic cycles.
67. Scientists have discovered how to put together a bacteriophage with the protein coat of
phage T2 and the DNA of T4. If this composite phage were allowed to infect an E. coli, then
phages produced by this cell would have what type of DNA and what type of protein? Of what
use is an envelope to a virus?
68. What is a retrovirus?
69. What is a viroid?
70. What is a prion?
71. How might viruses have originated?
72. What is genetic recombination?
73. What is the difference between conjugation and transposition?
Adapted from: http://www.horton.ednet.ns.ca/
Horton High School