Chapter 6-Microbial Growth & Nutrtion Lecture Notes

  1. What is the Chemical Requirement for Microbial Nutrition & Growth's Carbon source? (CO2) (2)
    • 1.) Autotroph
    • 2.) Hetertroph
  2. The Source of Carbon that
    -breaks down molecules from other organisms Carbons?
  3. This source of Carbon
    -"feeds itself"
    - uses an inorganic source of (CO2)
  4. Where do Microbial Nutrition & Growth get their Chemical Energy? (2)
    • 1.) Chemotroph
    • 2.) Phototroph
  5. What is the name of this chemical energy that requires Energy from
    Redox Reaction,
    fermentation &
    cell respiration?
  6. What's the name of the Chemical source that acquires energy from light?
  7. For Redox Reactions, where do they get the Chemical requirement for Electrons & H+ atoms? (2)
    • 1.) Lithotrophs
    • 2.) Organotrophs
  8. What Electron/H+ source is 
    -an Autotroph 
    -that acquires H+/E-1s (electrons) from INorganic molecules?
    -Formula (H2, NO2, -H2S, Fe2+)
  9. What is the formula for an electron/H+ source?
    H2, NO2 -H2 S, Fe2+
  10. What Electron/H+ source is 
    -a Hetertroph
    - uses same ORGANIC molecules as did for Carbon source?
  11. What are the NAMES of O2 that is Required for Microbial Nutrient & Growth?
    • 1.) Obligate Aerobe
    • 2.) Obligate ANAerobe
    • 3.) Faculative ANAerobe
    • 4.) Aerotolerant ANAerobe
    • 5)  Microaerophils
  12. What are the 4 TOXIC forms of O2?
    • 1.) Singlet
    • 2.) Superoxide radical
    • 3.) Peroxide anion
    • 4.) Hydroxl radical
  13. chart?chf=bg,s,00000000&cht=tx&chl=%5E1&chs=12x30What is the chemical formula for Singlet (toxic O2)?
    (1 O2)
  14. What is the Chemical formula for Superoxide Radical?
  15. What is the Chemical formula for Peroxide Anion?
    (O2 ^2-)
  16. What is the Chemical formula for Hydroxyl Radical?
  17. What does Superoxide dismutase do?
    it detoxifies superoxide radicals
  18. This TOXIC (O2 2-) is Hydrogen Peroxide formed during Reactions CATALYZED by Superoxide Dismutase
    Peroxide Anion (O2 2-)
  19. This ENZYME breaks down Hydrogen Peroxide without forming O2 using a Reducing Agent & happens during Superoxide Dismutase?
    & it's Rxn response?
    • Peroxidase
    • No Bubbles
    • H2 O2 + 2H+ ---> 2H2O
  20. This ENZYME converts Hydrogen Peroxide to water & moleculer O2
    & happens during superoxide dismutase
    & it's RXN response?
    • Catalase
    • Bubbles
    • 2H2O2 --> 2H2O + O2
  21. A TOXIC form of Oxygen, _____ oxygen, is molecular oxygen with electrons that have been boosted to an ^ Energy state.
  22. What is the other name for Superoxide Radical (O2-)?
    Because they are so reactive & toxic
    • Superoxide dismutase
    • (see card for formula)
  23. The most REACTIVE of the 4 TOXIC forms of O2 is _______.
    Hydroxyl Radical (OH·)
  24. Which terms best describes an organism that REQUIRES O2, it's essential?
    Obligate Aerobe
  25. Which of the following terms best describes an organism that cannot exist in the presence of O2?
    Obligate ANAerobe
  26. This ANAerobe maintains life in either NO O2 or with O2 & Decreased Metabolic Activity?
    Faculative ANAerobe
  27. This ANAerobe does NOT use O2, but can tolerate SOME O2.  What is it?
    ex: pickles in cucumbers & milk into cheese caused by lactobacili
    AEROtolerant ANAerobe
  28. This ____ requires low O2 levels of 2% to 10%.  What is it called?

    ex: ulcer causing H.pylori
  29. This___ requirement for microbial growth makes ^14% of Dry weight of cells & is growth limiting
    Anabolism will cease to build proteins or nucleotides
    it recycles old ones from amino acids & nucleotides
  30. What are the Physical Requirements to grow bacteria? (4)
    • 1.) temp
    • 2.) pH
    • 3.) osmolarity
    • 4.) pressure
  31. This ______ Requirement is important for 3-D shape
    -^temp, proteins denature
    -^temp, loose fluid membrane
    -Decrease temp=rigid & fragil
  32. The lowest temperature at which an organism is able to conduct metabolism is _____.
    minimum growth rate
  33. The highest temperature at which an organism continues to metabolize is called____.
    Maximum growth temp
  34. The Temperature at which an Organisms Metabolic activities produce the highest growth rate is called____.
    Optimum growth
  35. The Temperature within their Metabolic activity & Growth are best supported-microbes can be categorized into 4-over lapping groups called????
    • 1.) Phychrophiles
    • 2.) Mesophiles
    • 3.) Thermophiles
    • 4.) Hypothermophiles
  36. What are the _____ requirements that include:
    • pH
    • Neutral=7
    • acidophiles<7
    • alkalinophiles>7=base
  37. This temp group grows best @ temps below 15°-0°c
    -DOES NOT cause Human diseases
    -Lives  in snowfields, ice, cold H2O, icy waters
  38. This Temp group are organisms that grow best btwn 20°-40°c
    -cause human pathogens
    -cause food spoilage
  39. This temp group grows >45°c
    -does NOT cause disease
    -Find in Hotsprings
  40. This temp group grows in H2O >80°c is
    & find in Volcanos
  41. What are the physical effects of H2O?
    • 1.) osmotic pressure
    • 2.) Hydrostatic pressure
  42. This pressure on a membrane by a solution when a solute can't freely cross is called?
    osmotic pressure
  43. The lower the solute concentration outside the cell H2O goes in & swells up^ & bursts.  Is what type of Hydrostatic pressure?
  44. The higher the solute concentration outside the cell, causing H2O to be released, causing shrinkage.  Is what type of Hydrostatic pressure?
  45. What are the names of the Salt & Osmotic Pressure requirements for organisms that are restricted to certain environments? (2)
    • 1.) Obligate halophiles
    • 2.) Faculative halophiles
  46. This microbe likes HIGH osmotic pressure
    "they like the pressure on them"
    Obligate Halophiles
  47. This microbe doesn't require High osmotic pressure BUT can tolerate it
    ex: Staph on skin
    Faculative Halophiles
  48. This microbe is found living under conditions of HIGH Hydrostatic pressure is a __________.
  49. Name the 4 Types of General Media
    • 1.) Defined
    • 2.) Complex
    • 3.) Selective
    • 4.) Differential
  50. This medium provides EXACT known chemical composition & requires the (+) of a Large # of Growth factors
    Defined medium
  51. Which medium has an EXACT chemical composition that is unknown
    & contains nutrients released by partial digestion of yeast, beef, soy, or proteins
    & support growth of a wide variety of microbes-more widely used
    & ex: include____ Agar & ____broth
    & has the word "EXTRACT" in it?
    • Complex medium
    • ex: MacConkey Agar
    • Nutrient Broth
  52. Which medium contains substances that FAVOR the growth of One microbe or INHIBITs the growth of unwanted microbes?
    2 examples____Agar & ______Agar
    • Selective medium
    • Ex:  Mannitol Salt Agar=^SALT
    • Sabourand Dextrose Agar=Low pH
  53. Which medium do Microbiologists use to Distinguish among groups of bacteria that their presence of visible changes in the medium or Differences in the appearance of colonies.
    & ex_______Agar
    • Differential  medium
    • Blood Agar
  54. What is a Blood Agar?
    Agar with RBC in it
  55. What are the 3 examples in how an organism uses the RBC in Blood Agar?
    • 1.) Beta-hemolysis
    • 2.) Alpha-hemolysis
    • 3.) Gamam-hemolysis
  56. Which Hemolysis occurs on RBC Agar that completely digests RBC's?
    • Beta-Hemolysis
    • Spyrogenes
  57. Which hemolysis occurs on RBS Agar that partially digests RBC's?
    • Beta-Hemolysis
    • ex: S.Pneumoniae
  58. Which Hemolysis occurs on RBC Agar that does not digest RBC's?
    • Gamma-Hemolysis or hemolytic
    • ex: E. Faecalis
  59. Bacteria reproduce via_______ _______.
    Binary Fission
  60. What are the steps in Binary Fission?
    • 1.) Replicate DNA
    • 2.) Elongate
    • 3.) Form Septum
    • 4.) Seperate
  61. -Time Required for a single cell to grow & divide.
    -A population of microorganisms double during it's ____  ______.
    Generation Time
  62. How are bacteria growth represented on a chart?
    Logarithmic/ LOG scale
  63. What are the 4 phases of the microorganisms population growth?
    • 1.) Lag
    • 2.) Log
    • 3.) Stationary
    • 4.) Death
  64. This phase has
    -no growth
    -adjusting cells to environment
    -making enzymes
    is called what phase?
  65. This phase has a 
    -rapid chromosome replication  growth & reproduction
    -most susceptible to Abx
    -Best for Gram Stain
    is Called what phase?
  66. In this phase 
    -new organisms are being produced at same rate as dying
    # of dying cells=# of cells reproduced
    -No nutrients left
    -No place
    what phase is this?
    Stationary phase
  67. In this phase organisms/cells are dying more quickly than they can be replaced.
    what phase is this?
    Death phase
  68. How do we measure Microbial reproduction counts? (3)
    • 1.) Microscopic Counts
    • 2.) Plate Counts
    • 3.) Membrane Filtration
  69. This count is useful for 
    -stained prokaryote & large eukaryotes
    -DIRECT method
    -count through a microscope
    Is called?
    Microscopic counts
  70. What is the advantage to Microscopic counts?
    Advantage: No incubation time
  71. What is the disadvantage to Microscopic counts?
    • 1.) can't differentiate btwn living/dead cells
    • 2.) motility
    • 3.) High cell concentration
    • 4.) Time consuming
  72. This count is useful for serial dilutions & counting bacteria on a plate & most commonly used.
    what is it?
    Plate counts with Serial Dilutions
  73. What is the advantage of Plate counts?
    most commonly used method
  74. What is the disadvantage of Plate counts?
    • 1.) Ability to grow on Selected Medium
    • 2.) Growth phase is important
  75. For plate counts
    65 X 10 X 1000= bacterial cell growth
    How many colonies do you want to have to do the viable plate count?
    # of colonies x dilution form o.1ml x10 fold dilutions= 650,000(count the zeros)

    25-250 colonies
  76. This type of count is used when population density of microbes is too small
    sample poured through a filter & filter traps bacterial cells
    Membrane filtration
  77. What are the advantages of membrane filtration?
    looks @ living viable cells
  78. Which measurement is an INDIRECT method for estimating the # of microbes in a sample?
    -measure with a spectrophotometer
    -cloudiness=bacterial growth
Card Set
Chapter 6-Microbial Growth & Nutrtion Lecture Notes
Lecture Notes