Microbiology Midterm

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Microbiology Midterm
2010-10-03 07:30:31

Dr. Parks Microbiology Midterm
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  1. What are Koch's posulates?
    • 1. The organism must be present in every case of the disease
    • 2. The organism must be isolated from the dieseased host and grow in pure culture
    • 3. The disease must reproduce when a pure culture of the organism is innoculated into a healthy suceptible host.
    • 4. The organism must be recoverable from the experimentally infected host.
  2. Hooke
    • Found living shings are made up of cells through observations of mold fruiting bodies.
    • First ever to focus on microscopy
    • - The germ theory of disease - microorganisms are the casue of infectious diseases

    First book written on microorganisms
  3. Who is considered the father of microbiology?
    • Anton von Leeuenhoek, becasue he constructed his own microscope which allowed him to see beacteria which was much smaller than the molds he was looking at
    • - first person to see bacteria
  4. two big questions of early microbiology
    • does spontaneous generation occur?
    • what is the nature of infectious disease?
  5. can all vassillis be killed by boiling
    no they need to be pressurized and heated
  6. Louis Pasteur

    Two accomplishments
    Debunked theory of Spontaneous Generation Introduced concept of "diseases" in wine/beer caused by microorganisms

    Pasteurization - Process of gentle heating to inactivate contaminating microbes

    Swann neck flaskflask - with a narrow opening which was boiled to sterilize and then neck bent. Air gasses allowed to pass through but dust particles could not get in
  7. Paul Ehrlich
    • First to treat syphilis with Salvarasan; introduced concept of chemotherapy
    • - taught that microorganisms react differently with different chemicals
  8. Robert Koch
    First person to isolate a causative agent of an infections disease
  9. Edward Jenner
    Created vaccination using idea that milkmaids never got cow pox because they were exposed to it and therefore introduced the idea of vaccination.
  10. Microbiology is the study of.....
    microscopic organisms and viruses and thier roles in human disease as well as beneficial processes
  11. Eukaryotic
    Having cellular structures enclosed by membranes. "Eu" means true. Karyote = nucleus.
  12. Prokaryotic
    No distinguishable membraneous stuctures. "Pro" means before
  13. Big ideas in infectious disease study
    • 1. Microscopes
    • 2. Pure cultures for isolating pathogens
    • 3. Germ theory of disease
    • 4. antiseptics
    • 5. scientific rigor
    • 6. chemotherapies and antibodies
  14. 3 main domains of life
    • bacteria, archaea, and eukaryotes
    • - largest group is prokaryotes but archaea is closer related to eukarya than it is to bacterium
  15. Macromolecule
    • Very large compounds:
    • 1. proteins
    • 2. sugars
    • 3. nucleic acids
    • 4. lipids
  16. Shapes
    1. circle or sphere
    2. a spiral shape
    3. long cylindrical shapes
    4. long, winding spirals (thinner and longer)
    5. bent
    6. stalks, looks like a push pin or tack
    7. multiple long pin like structures clumped together
    • 1. coccus
    • 2. spirrilum
    • 3. rob/bacillus
    • 4. spirochetes
    • 5. vibrio
    • 6. appendaged
    • 7. filamentous
  17. What are the 2 groups of non-living organisms?
    1. Viruses, satellite viruses, viroids2. Prions
  18. What are the 6 kingdoms of life?
    • 1. Animalia
    • 2. Plantae
    • 3. Fungi
    • 4. Protista
    • 5. Eubacteria
    • 6. Archaebacteria
  19. What are 2 factors that distinguish the living from the non living?
  20. 1. They do not have cells
    2. They do not reproduce
  21. diplo
    • 2
    • chains
    • 4
    • cube or 8
    • grape like cluster
    • a bacillus which appears almost circular
  22. cell sizes
    - smallest
    • - nanobacteria which meets the lower limit of 0.1 of a micrometer
    • - thomargarita at 750 micrometers (it is so big due to a large sulfur vesicle in the center of it)
  23. Gram negative
    thin peptidoglycan layer that can be easily destained and turned red when treated with saffranin
  24. gram positive
    thick peptidoglycan layer that turns purple when subjected to crystal violet staining
  25. steps in gram staining
    • 1. add crystal violet - all purple
    • 2. grams iodine - crystallizes the purple
    • 3. EtOH or acetone - decolorizes gram negative
    • 4. saffranin - gram positive will be purple but gram negative will turn red
  26. the acid fast test
    • used to tell id a cell has a mycolic acid layer as opposed to a peptidoglycan layer. These cells are technically gram positive but will not stain becasue they lack the necessary peptidoglycan to retain the crystal violet stain
    • - these mycobacterium dont have cell walls which allows them to be slow growing and resistant to most antibiotics

    - basically allows us to see which cells are like this so further action can be taken to liberate the host
  27. Trophs
    - examples
    • Defines where energy comes from/ where carbon comes from
    • 1. chemicals - (chemo-)
    • a. organics - chemoorganotrophs
    • b. rocks - chemolithotrophs
    • 2. light - phototrophs
    • 3. organic chemicals - heterotrophs
    • 4. inorganic chemicals - autotrophs
  28. Obes
    - examples
    • Defines whether or not organisms need oxygen or need to be separated from oxygen
    • 1. anarobes - need to be separated from air

    2. aerobes - need to be surrounded by air

    • a. obligate - have to have
    • b. facultative - can tolerate
  29. philes
    - types
    • describes the environments and conditions organisms "love"
    • 1. salt - halophile
    • 2. temperature
    • a. high temp - hyperthermophile
    • b. low temp - psychrophile
    • 3. pH
    • acidic - acidophile
    • basic - alkaliphile
    • 4. pressure - barophile
  30. Essential Components of Life
    • 1. must metabolize
    • break down - catabolism
    • build up - anabolism
    • 2. reproduce
    • 3. differentiate
    • 4. evolve
    • 5. movement
    • 6. communication
  31. why isnt a virus alive?
    becasue it need a host in order to reproduce
  32. Lipids
    large, non-polar, organic molecules do not dissolve easily in water

    -used for fuel energy and structureal components
  33. Vitamin
    organic cofactor (Not a macromolecule; often organic) that cannot be made by the cell that requires them

    Ex. humans need calcium.
  34. Carbohydrate (polysaccrides)
    • organic compounds made up of carbon, hydrogen, and oxygen (sometimes other elements)
    • -serve as: building blocks for other macromolecules, storage compounds, modify function of proteins "added water to carbon"
  35. nucleic acids
    (RNA,DNA, nucleotides)

    • RNA and DNA are used for catalytic processes and information storage
    • Nucleotides arre useed for the transfer of energy and signalling
  36. amino acids (peptides and proteins)
    used for energy, catalysts, signalling, structural intermediates and many other things
  37. Allowed through cytoplasmic membrane
    glycerol, water, small uncharged molecules, animo acids, glucose
  38. not allowed through cytoplasmic membrane
    salt,big things, charged things, ions
  39. ways for other molecules to get through cytoplasmic membrane
    • channels - selective
    • integral/transport proteins - selective
    • porins - not selective
  40. proton motor force
    • bacteria pump hydrogen ions outside of the cell constantly but they need there hydrogens in order to power the production of ATP
    • - so, as the hydrogens are forced out and we get an ion gradient that creates a force that can be used by ATPase to make more ATP
  41. 2 ways bacteria move
    tumble - when tconcentration of nutrients is low and they tumble around

    straight line - if there is a high concentration of nurtients

    to whip in a circular motion - alternate clenching and relaxing
  42. ampipathic phospholipids
    both hydrophobic and hydrophilic parts
  43. Capsule and slime layer -

    Polymer of sugar residues that coat the bacterium or eykaryote (used for protection or for a sticky adherence to things)

    EPS - extra polymeric substance
  44. fimbria and pilli
    • Attachment hooks that the organism can use to "hold on" to things
    • - pilli are specialized, fimbria are not (sex pilli)
    • - pilli used in twitching/ inch worm motility
  45. flagella
    1. trichous
    4. polar
    5. lopho
    6. amphi
    • Movement and motility
    • 1. projections
    • 2. one
    • 3. all over
    • 4. at one or both ends
    • 5. tufted
    • 6. both
  46. Flagella are anchored by _____
    grow from _____ (not like_______)
    move with __
    • basil bodies
    • tip, not like hair from a root
    • energy from the proton motor force to pull cell forward ( gliding motility)
  47. chemotaxis
    • movement of an organism towards or away from a chemical
    • movement to or from light
    • movement to or from oxygen
  48. inclusions
    • Inclusions are dense aggregates of specific chemical compounds in the cell.
    • Typically, the aggregated chemical serves as a reservoir of either energy-rich compounds or building blocks for the cell.
    • Forming polymers costs energy and it may seem wiser for the cell to keep the excess monomers around for when they are needed.

    However, the role of some inclusions is unclear. Growth on rich medium causes their creation, but subsequent starvation in the test tube does not always result in the use of these reserves. This suggests that these inclusions, at least, are not storage bodies.
  49. endospores
    • These form when there is a low concentration of nurtients needed for continuation of life. They are super resistant and always show as gram +
    • - these are a way for the organisms to propogate itself because it can now protect its dna from degregation through this long lived endospore
    • - they have an acid protected shell for the DNA and itself
  50. parameters of growth
    Growth can only happen in the presence of nutrients. As nutrients decrease and waste increases, the cells will begin to die. It will then lyse out its remaining nutrients to endospores or other organisms. this allows those organisms to start growing again
  51. fermantation
    • substrate level phosphoylation
    • gives off 4 ATP
    • - Used when alot of ATP is not needed or in the absence of ATP
    • a. products - acids
    • b. glycolysis gives off c-c-c needed for respiration
  52. Respiration and electron transport chain
    Use the proton motor force to generate the H+ gradient needed in ordwer to power the production of maximum ATP (38)
  53. redox reactions
    show where electrons come from and to whom they are donated
  54. doubling time
    • the time needed for the cell count to double
    • - this is during the exponential growth section of the phases of growth
  55. central dogma
    dna -> RNA -> proteins

    • 1. replication - DNA converted into new double stranded DNA using DNA polymerase
    • 2. Transcription - DNA is converted to mRNA using RNA polymerase
    • 3. Translation - mRNA is encoded into the new fully functional protein using the ribosomes
    • - ribosomes are aided by tRNA and tmRNA
  56. tmRNA
    • used to unstall ribosomes and encodes the degredation of proteins made by a messed up ribosome
    • - functional and information starage protein
    • a. carries alanine - storage of information
    • b. encode degregation - function
  57. MREB
    • primitive cytoskeleton
    • - helps make structure, without it we have sphere shape and with it we have rod shape
    • - the scaffolding also helps localize certain functions to happen in only one part of the cell
  58. information storage proteins
    those that carry amino acids and other information sequences
  59. functional proteins
    proteins that carry on metabolic, catalytic, or other processes (are reactive)
  60. there are 2 different types of DNA strands
    • leading strand - made continuously by polymerase
    • lagging strand - is not in the right orientation to be made continuously and therefore must be made in okazaki sequences
  61. steps of transcription
    • Initiation (requres sigma factors)
    • elongation
    • termination
  62. Sigma factors
    • sigma 70- general housekeeping
    • sigma 38- stationary phase
    • sigma 32- heated shock
  63. types of termination
    • intrinsic - stem loop
    • RHO dependent - recognizes the RHO terminator
  64. translation of mRNA to protein
    • 1. The 16s subunit of ribosome recognizes the SHINE DELGARNO sequence which allows for ribosomes to bind
    • 2. tRNA is now able to bring anticodon to the transcript, thus assembling a new protein
    • 3. The code is redundant = there is more than one code for each amino acid this way mutation wont always be devistating
  65. nonsense codon
    stop codon
  66. translation is driven by
    GTP - this is becasue it has the same amount of energy as ATP, but is less abundant, letting us know that if we start to run out of GTP we need to stop/slow down so the cell doesnt run out of ATP
  67. 4 steps of translation
    • 1. Initiation
    • 2. elongation
    • 3. translocation - GTP powered
    • 4. termination
  68. chaparonins

    cells communicate
    make sure things stay folded properly

    in response to their environment using signals
  69. global control
    the regulation of more than one process
  70. microbial ecology

    Microbial populations
    study of microorganisms in their natural environments

    Groups of cells derived from a single parent cell by successive cell divisions
  71. Infectious diseases are caused by
  72. enrichment culture technique
    microorganisms are isolated from natural samples ina highly selective fashion by manipulating nutrient and incubation condidtions
  73. Problems with microscopy
    • alive or dead?
    • hard and time consuming

    - live and dead staining techniques (sees if the membrane has been depolarized or not)
  74. flow cytrometry
    problems- cannot deal with more than one or 2 bacteria and expensive

    solution - count cells by dilutions
  75. turbidimetric
    Depends on how cloudy media is

    • Problems - can only look at one organism
    • depends on organisms environments
  76. Transcription initiator complex
    waits for initiators to start

    makes polymer of RNA (which can form secondary structure

    separates 2 DNA strands to make new RNA
  77. corum sensing
    • bacteria can "talk"
    • - when they are together they recieve each other's sign als and are able to see how many of them exist and can then make a move all together
    • - auto inducer 1 - species specific
    • - auto inducer 2 - interspecies
  78. competitive inhibition

    Why better than antibiotics
    blocks receptor with a similar molecule

    by killing bacteria we are only allowing the resistant forms to live which does not stop the damage they do. if we inhibit them, we keeo them from talking to each other
  79. different types of media
    culture media - nutrient solutions used to grom microorganisms in the laboratory

    defined media (selective) - prepared by adding precise amounts of highly purified inorganic or organic chemicals to distilled water

    Complex media - highly nutritious yet impure substances (usually better)
  80. chemical compartmenalism
    using GTP instead of ATP for certain functions (ribosomes use GTP for translocation)