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2011-07-25 02:24:44

Study cards for DNA chapter
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  1. List the three characteristics that early scientists knew genes must posess.
    • ability to store information
    • information must stable enough to pass on
    • information must be able to mutate
  2. If genetic information was not stable it would ______ over time.
  3. True or False - Genetic mutations provide for genetic variability and are essential for evolution.
  4. List the two acid components that were found as part of the genetic material.
    • ribonucleic acid
    • deoxyribonucleic acid
  5. Who performed important research with Streptococcus pneumoniae?
  6. What bacteria strain did Griffith use in his bacterial transformation experiments?
    Streptococcus pneumoniae
  7. What two strains of Streptococcus pneumoniae did Griffith find?
    The S strain and the R strain
  8. Which strain of streptococcus has a capsule, S or R?
    the S strain
  9. The R strain of Streptococcus pneumoniae has what sort of exterior characteristic, smooth or rough?
  10. The main difference between the R strain and the S strain is the absence of a:
  11. What happened to the mice injected with S strain strep?
    they died
  12. What happened to mice injected with R strain strep?
    they lived
  13. True of False - The S strain of streptococcus is pathogenic while the R strain is not.
  14. What happened to the mice injected with "heat-killed" S strain strep?
    they lived
  15. What happened to mice injected with "heat-killed" S and R strain strep?
    they died
  16. A change in genetic makeup due to the assimilation of foreign DNA is known as:
  17. List the four nucleotides found in DNA.
    • adenine
    • guanine
    • thymine
    • cytosine
  18. Which nucleotides are purines?
    • adenine
    • guanine
  19. Which nucleotides are pyrimadines?
    • thymine
    • cytosine
  20. How were nucleotides originally thought to pair up?
    like bases would pair
  21. What would happen if two purines paired up?
    they would be too long for the DNA ladder
  22. If two pyrimadines paired they would be too ____ for the DNA ladder.
  23. A purine is ________ than a pyrimadine.
  24. How do nucleotides actually pair up?
    purine + pyrimadine
  25. What are Chargaff's Rules?
    • The total amount of each nucleotide will vary between organisms
    • In a specific organism, the amount of A=T, and the amount of C=G
  26. Do humans have more A/T pairs or C/G pairs?
    A/T pairs
  27. Who first constructed the DNA double helix model?
    Watson and Crick
  28. What sugar is part of the DNA backbone?
  29. What basic shape is deoxyribose?
    a pentagon
  30. The backbone of DNA is comprised of what two molecules?
    deoxyribose and phosphate
  31. Deoxyribose is a ______ carbon sugar.
  32. How are the carbons in deoxyribose numbered?
  33. At which carbon of deoxyribose will the phosphate attach?
    5' carbon
  34. How does one sugar-phospate attach to the next sugar-phosphate?
    phosphate bonds covalently with the 3' carbon of the next sugar
  35. The orientation of DNA strands is:
  36. The nucleotide base pairs attach to which carbon of deoxyribose?
    the 1' carbon
  37. What type of bond connects complimentary nucleotide bases?
    hydrogen bonds
  38. Because the parent strand of DNA separates and acts as a template for the daughter strand, DNA replication is said to be:
  39. What is an origin of replication?
    starting point for replication
  40. How many origins will a eukaryotic chromosome have?
  41. As the DNA strands pull apart from the origin, they form:
    replication bubbles
  42. The point at which the DNA strand is pulling apart as replication moves outward is known as the:
    replication fork
  43. What enzyme unwinds DNA?
  44. The molecule that binds to, and keeps the DNA strands separated after helicase unzips them is:
    the single strand binding protein
  45. What is the role of topoisomerase?
    moves ahead of helicase, breaking hydrogen bonds and relieving tension in the strand
  46. True or False - Hydrogen bonds remain broken after topoisomerase breaks them.
    False - they reform and hold until helicase breaks them again
  47. What is needed in order for DNA replication to start?
    a primer
  48. What is the function of primase?
    to manufacture the short RNA primer
  49. The RNA primer needed to start DNA replication is produced by:
  50. Where the RNA primer attaches becomes the _____ prime end of the daughter strand.
  51. DNA poly III can only add nucleotides to which end of the daughter strand?
    the 3' end
  52. A new DNA strand always forms in which direction?
    5' to 3'
  53. The 5' to 3' parent strand is known as the:
    leading strand
  54. The 3' to 5' parent strand is known as the:
    lagging strand
  55. The strand that replicates continuously towards the replication fork is the:
    leading strand
  56. The strand the replicates away from the replication fork in a series of fragments is the:
    lagging strand
  57. What are the three steps of leading strand replication?
    • DNA polymerase III attaches the appropriate nucleotides
    • DNA polymerase I strips off the RNA primer and replaces it with DNA nucleotides
    • DNA ligase fills in phosphates, connecting the DNA backbone where primers were removed
  58. True or False - When the lagging strand fragment reaches an RNA primer, the DNA poly III will detach and move backwards past the previous primer and start a new fragment.
  59. What enzyme adds nucleotides to the new DNA strand?
    DNA polymerase III
  60. What enzyme will fill in the blanks after the primers are removed?
    DNA polymerase I
  61. After the primers are removed and replaced with DNA nucleotides what enzyme will add phosphates and connect the DNA backbone?
    DNA ligase
  62. The small fragments of nucleotides created in the 5' to 3' order on the lagging strand are known as:
    Okazaki fragments
  63. At the ends of chromosomes are sequences of genetic nonsense called:
  64. Because DNA poly III cannot add nucleotides to the 5' end of a strand, this enzyme adds telomeres to the ends of DNA strands which can be clipped off.
  65. What enzyme proofreads and removes any incorrect nucleotides from a DNA strand?
  66. What two things happen when an error is found in the replicated DNA strand?
    • nuclease clips out the incorrect nucleotides
    • DNA poly III adds the correct sequence