The flashcards below were created by user asia.biles on FreezingBlue Flashcards.

  1. What are the two chemical components of the chromosome?
    DNA and protein
  2. What are viruses that exclusively infect bacterial cells called?
    bacteriophages (phage)
  3. What is T2?
    Bacteriophage that targets E coli.
  4. How did Hershey and Chase determine that genetic material was associated with DNA and not protein?
    By using radioactive sulfer to attach to the proteins and radioactive phosphate to attach to DNA in two different experiments. This allowed tracing of the spread of the radioactive material.
  5. What is the importance of a polynucelotide?
    They are the polymer of nucleotides, which build DNA and RNA
  6. Name the different nitrogen bases for DNA.
    Adenine, cytosine, thymine, and guanine.
  7. What components make up each nucleotide?
    Sugar, nitrogen base and phosphate group.

    * Nucleotides have a sugar-phosphate backbone
  8. What type of bond holds nucleotides together?
    Covalent bonds
  9. Why is DNA called deoxyribonucleotide?
    Because the sugar in nucleotides contain one less sugar than normal ribose sugar found in RNA.
  10. What type of bond holds nucleotide base pairs together?
    Hydrogen bonds
  11. What are purines and pyrimidines?
    • Both purines and pyrimidines make up the structure of the four DNA nucleotide bases. 
    • Purines are large, double-ringed structures making adenine and guanine. 

    Pyrimidines are smaller single-ringed structures that make up thymine and cytosine.
  12. What type of structure do thymine and cytosine have?
    They are pyrimidines, single-ringed
  13. Which of the four DNA nucleotide bases are considered purines?
    adenine and guanine are large, double ringed nucleotides
  14. What is the difference in nucleotide bases between DNA and RNA?
    RNA has uracil instead of thymine.
  15. Which base-pair combination is somewhat stronger than the others? Why is this?
    C-G base pair is stronger because it has three hydrogren bonds.
  16. What is the semiconservative model?
    The semiconservative model occurs with DNA because half the parental molecule is conserved in each daughter molecule
  17. Where does DNA replication occur?
    At the origin of replication
  18. Briefly describe how DNA replication occurs/starts.
    At origins of replication, proteins that initiate DNA replication attach and separate the strands of double helix. Replication proceeds in both directions creating "bubbles." The parental strand opens and the daughter strands elongate.
  19. What is the strutural difference between the 5' and 3' carbon groups?
    3' carbon is attached to OH group, while the 5' carbon is attached to a phosphate group.
  20. What is important about DNA polymerase in the production of a daughter DNA strand?
    DNA polymerase links nucelotides to the 3' end of the growing strand

    DNA polymerase also proof reads the nucleotides to make sure that the base-pairing is correct.
  21. What direction does a DNA daughter strand grow?
    DNA polymerase adds nucleotides only to the 3' end of the strand, meaning that the daughter strand only grows from 5' to 3'
  22. What are Okazaki fragments?
    short segments of strands that are synthesized after the fork where the DNA opens up.
  23. What links together the two DNA strands after the okazaki fragments are complete?
    The DNA ligase links/ligates the two DNA strands together into a single DNA strand.
  24. What is involved in repairing DNA after exposure to harmful radiation?
    DNA ligase and DNA polymerase
  25. DNA replication ensures that all the _____ cells in an organism carry the same ____ information
    Somatic cells; genetic information
  26. What are the two major overall stages in building protein from DNA?
    Transcription and translation
  27. Does DNA or RNA use U instead of T?
    RNA uses U
  28. During what stage is DNA rewritten onto RNA is a different type of codon language?
  29. How many nucleotides make up one codon ("code" for one specific amino acid)?
    Codons are composed of three nucleotides. This allows for 64 possible code "words," which is plenty for the 20 present amino acids
  30. What is significant about the codon AUG?
    AUG codes for both the amino acid methionine (Met) and for the start of a polypeptide chain. 

    *AUG is the only codon to code for the start of a polypeptide chain.*
  31. What codons code signify the end of a polypeptide chain?
    UAA, UGA and UAG
  32. What is different about the codons UAA, UGA and UAG?
    These codons signify the end of the polypeptide chain!
  33. __________ is a reminder of the evolutionary kinship that connects all of life on Earth.
    A shared genetic vocabulary.
  34. Where does transcription take place in Eukaryotic cells? What about prokaryotic cells?
    Transcription takes place in the nucleus of of eukaryotic cells and in the cytoplasm(??)
  35. What is the role of RNA polymerase in prokaryotic cells?
    RNA polymerase is a transcription enzyme that helps form the new RNA strand by following the base-pairing rules (but replacing thymine with uracil). RNA polymerase starts adding nucleotides at the binding side (promoter) and ends at the terminator (code for end of gene).
  36. What type of RNA encodes amino acids?
    mRNA (messenger RNA)
  37. What is the function of mRNA? Where does it do its work?
    mRNA is transcribed from DNA and the information is translated into polypeptides. The mRNA is formed inside the nucleus but is edited (introns are removed via RNA splicing so that only exons remain) before traveling to the cytoplasm.
  38. What kind of processing occurs the the mRNA before leaving the nucleus to go to the cytoplasm?
    • 1- Extra nucleotides are added to the ends of the RNA transcript (small cap at the 5' and tail at the 3')
    • 2- Removal of introns ("nonsense words") via RNA splicing to leave just the exons (coded regions)
  39. Aside from the removal of introns from the mRNA, what important benefit does RNA splicing have?
    It allows production of multiple polypeptides from one single gene (this is a huge factor in creating many many thousands of polypeptides from our 21,000 genes.
  40. What is the first important ingredient for translation?
    • Processed mRNA! 
    • enzymes and chemical energy source (ATP) is also needed
  41. What does the combination of deoxyribose sugar, phosphate group and a nitrogen base make up?
    A nucleotide!
  42. How do codons become translated to proteins?
    Via tRNA (transfer RNA). tRNA matches the correct amino acid with the correct codon to form polypeptides.
  43. Describe the structure of tRNA
    tRNA is a single-stranded loop containing an anticodon on one end (complimentary to the codon on mRNA). On the other end of the tRNA is a site were one type of specific amino acid attaches.
  44. True or false, there is just one type of tRNA for all types of amino acids.
    False! all tRNA molecules are similar, but each amino acid requires a slightly different variation.
  45. Where does growing of the polypeptide and transformation into protein occur?
    In the ribosome structures!
  46. Describe the structure of ribosomes.
    Ribosomes are made up of proteins and a type of RNA called ribosomal RNA (rRNA). There are two subunits: one is large and one is small.
  47. What is the difference between bacterial and eukaryotic ribosomes? Why is this important?
    bacterial ribosomes are smaller than eukaryotic ones, with a slightly different composition. Certain antibiotics deactivate ribosomes, leaving the eukaryotic ribosomes unaffected. Tetracycline is an example.
  48. What type of binding sites are found on ribosomes? Where are these binding sites located?
    The small subunit contains a binding site for mRNA and the large subunit contains binding sites (P site and A site) for the tRNA.
  49. Which ribosome binding site does the initial tRNA attach to?
    On the large subunit to the P site.
  50. Page 197, 10.14
Card Set:
2016-02-23 01:22:44
cellularbiology cellular biology
Bio 211
Ch 10 Bio 211: Molecular biology of the gene
Show Answers: