Micro exam 2

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Micro exam 2
2011-10-26 20:44:11
Microbiology Exam

Viruses, microbial genetics and prions
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  1. Mutagen
    is chemicals or radiation that can increase the frequncy of mutations (at least 1,000 fold)
  2. Vertical gene transmission
    is a mother cell replicating DNA and then giving it to the daughter cell
  3. Horizontal gene transfers
    Is genes transferring from one cell to another (3 different types)
  4. Base substatution
    when one base pair is changed (also called a point mutation)
  5. insertion
    is when a random nucleotide is added into the nucleic acis so this causes a base shift since it throughs off the 3 codon protein producing
  6. Deletion
    is when one nucleotide is taken away from the DNA/nucleic acid causing a base shift which really messes up the 3 codons
  7. Silent mutation
    when a new nucleiotide is put in that was a mutation but it still codes for the same amino acid so nothing changes even though there was a mutation
  8. Missense mutation
    When the mutation codes for a different amino acid then was origanlly supposed to be coded. can lead to badness
  9. nonesense mutation
    when the new mutation codes for a stop codon so that the original amino acid isn't produced nor is any amino acids after it. this does lead to badness
  10. knockout mutations
    is a drastic nonsense mutation. It stops the production of the protein before it can even get started so nothing is made
  11. prototroph
    makes all the 20 essential amino acids without enviromental help
  12. auxotroph
    it can't make one or more of the 20 essential amino acids so it has to get the amino acid from the enviroment to be able to survive
  13. superoxide radical (O2-) and H2O2
  14. the O2 oxidizes guanine before and after it has been incorporated into DNA and DNA polymerasse often mispairs the oxidized guanine with adenine rather then cytosine, causing a point mutation
  15. alkylating agent
    adds alkyl groups (CH3 and others) to the nitrogenous bases such as guanine which creates a base substatution.
  16. base analog
    incorporates in place of normal nucleotide in DNA which results in a base
  17. intercalating agent
    inserts between base pairs in either the template or the new strand resulting in an addition or deletion of the base pairs
  18. X rays
    single and double strand break in DNA resulting in deletion of bases
  19. Ultraviolet radiation
    intrastrand thymine dimer formation resulting in base substatution resulting in base substatution.
  20. excision repair enzymes
    If you don;t have them then you easily sunburn get them from the notes when you get your laptop back :(
  21. Fixed light repair system
    Only bacteria can do this but it's when visible light activates enzymes to break down thymine dimers that the Uv light created
  22. SOS repair system
    When the bacteria is super damaged it releases a enzyme that activates this SOS repair system which starts polymerase V (umuD gene is the gene that produces the poly 5, RecA protein is the protein that was released from the damaged DNA which turns off the LExA protein that is the restriction protein in the umuD gene) to fill in the blanks that poly 3 couldn't do because of the thymine dimers. The 5 just goes in and fills in so lots of mistakes and doesn't proofread so lots of mutations but better then a whole bunch of deletions
  23. transformation
    is when a single DNA is just floating around and gets incorporated into a living cells DNA (this the mice and getting sick)
  24. transduction
    When a virus infects a bacterial cell and incorporates it's viral DNA into the host cells DNA
  25. Conjugation
    When a cell with a sex pili (f Factor) transfers it's plasmid DNA into a cell that doesnt have the F factor
  26. Frederick griffith
    came to the conclusion that bacteria preform transformation with his experiment with mice. Only encapsulated living bacteria can kill the mice, so if you mix dead encapsulated bacteria with living unencapsulated bacteria you will get a killer encapsulated bacteria (because through transformation the living unencap. cells pick up the DNA from the dead encap. cells and the living cells become encapsulted and deadly)
  27. Bacterial compentent
    • It means that the recieving cell is in a specific physiological state that allows DNA to enter a cell (transformation).
    • Some species are always competent
    • some become competent because of special enviromental conditions (like when there's certain nutrients in the envirment or when the population reaches a critical density)
  28. electoporation
    a electical current is applied to a bacterial cell that isn't competent so that becomes competent and can take up other DNA
  29. Transcription
    a molecule of DNA is used to construct a molecule of mRNA (needs RNA polymerase)
  30. Translation
    a molecule of mRNA is used to construct a protein molecule
  31. DNA replication
    A molecule of DNA is used to construct a molecule of identical DNA (needs DNA polymerase)
  32. promoter region
    during transcription is helps the RNA where to bind to on the DNA
  33. Nucleotide O
    Same code in every cell , it's between the promoter and the gene
  34. Sigma factor
    A protein that binds to RNA polymerase (transcription) and helps the RNA polymerase bind to the promoter region (found in prokaryotic cells only). There are different sigma factors none are identical so that it only binds to just the right RNA polymerase so that the right protein is made
  35. Monocistronic mRNA
    The only type the eukarytocs do, it's only on gene for one protein with one promoter and one terminator
  36. Operon
    A group of genes that share the same promoter and terminator (creates polysistronic mRNA) Only found in prokarytoes
  37. poly G caps
    are added to mRNA of eukaryotic cells only
  38. Poly A Tails
    are added to mRNA of eukaryotic cells only
  39. introns
    are found in the mRNA or eukaryotic cells only
  40. Start codons are found on..
    mRNA so that the ribsome knows when to start to assemble amino acids
  41. Ribosome binding sire are found on...
    mRNA they help get the ribosome binded to the mRNA so they can start producing amino acids
  42. Stop codons are found on the...
    mRNA to break off te covalent bonds between the mRNA and the ribosome so that they can break off and stop making amino acids
  43. Bacteriophage
    Attacks bacterial cells it has a tail region that injects or poops the nucleic acid into the cell
  44. animal virus
    attacks animals cells, it has a capsid protein coat but it might also have a matrix protein and or a envelope made of phospholids (from budding)
  45. Sense (+) RNA
    has both a start codon (AUG) and a ribosome binding sight (AGGAGG) it can make a protein right away off of it.
  46. Antisense RNA (-)
    • Can't code for a protein right away you have to make a complemetary peice of RNA which will then be sense RNA (+) and that can be read for proteins.
    • (this is what HIV has that's why it is a retrovirus)
  47. Antisense DNA (-)
    Doesn't have AGGAGG or AUG but if you make a RNA from it you get sense RNA
  48. Sense DNA (+)
    has AGGAGG and AUG but you can't make a protein of it sense only RNA can do that. you would have to make a complement of this DNA which give you a antisense DNA and then from there make a RNA that would then give you a sense RNA.
  49. excursion
    It's when a productive bacteriophage assembles all the new viruses into the membrane of the bacterial host cell and they live from there not killing the bacterial host cell in the process.
  50. Early Genes
    For a productive bacteriophage it's the first 2 genes that need to made right after the nucleic acid is injected. They are nuclease which breaks down the host cells chromosomal DNA and then the polymerase gene needs to create polyemerase so that it can start replicating the viral nucleic acid right away.
  51. Prophase
    the name of the virus when its in lysogen and it's kjust a latent infection
  52. Temperate bacteriophage
    is a virus that causes a latent infection
  53. Lysogen
    the name of the infected bacterial host cell that has the prophage
  54. Endocytosis
    when a animal virus binds to a receptor and it has the right bond to bind to it, it tricks the animal cell into thinkning it's food and it gets opposite of enveloped in.
  55. fushion
    when a enveloped animal cell binds on to the membrane of the animal cell then fuses with membrane and plops in and decoats
  56. Budding
    When a animal cell leaves a cell and takes part of it's membrane (giving the virus a envelope) and not killing the animal cell host.
  57. Herpes virus
    doesn't go into the host cells DNA but when it's latent hangs out in the cytoplasm of a nerve cell, when stress like sunburn or menstration stress it out it leaves and has a productive infection with epithelial cells
  58. restriction enzyme
    a bacterial cell produces it so that it can cut up viral DNa before it can get into the host cells DNA. It knows the difference between the viral DNA and the own DNA by the presences of methyl groups (CH3) on the DNA