Test 3

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Test 3
2013-04-17 23:11:48

Microbiology, IVCC, Mr. Nett, Test 3
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  1. Refers to the number of bacteria cells, not the size
    Microbial Growth
  2. Name two general requirements for microbial growth
    Physical and Chemical requirements
  3. Identify three specific physical requirements of microbial growth
    Temperature, pH, Osmotic Pressure
  4. Cold Loving Bacteria
  5. What temperature do "cold loving" bacteria enjoy?
    0 - 20 degrees Celsius
  6. Moderate temperature loving bacteria
  7. What temperature do "moderate temperature" bacteria enjoy?
    20 - 40 degrees Celsius
  8. What is the most common temperature group can bacteria be found in?
    Mesophile, 20-40 degrees Celsius
  9. "Heat Loving" bacteria
  10. What temperature do "heat loving" bacteria enjoy?
    40-100 degrees Celsius
  11. What pH levels do most bacteria grow at?
    6.5 - 7.5
  12. Very few bacteria tolerate what pH level?
  13. This bacteria causes stomache ulcers, releases urease.
    Helicobacter pylori
  14. pH can be associated with food preservation from spoilage. How?
    Acids produced during fermentation prevent food spoilage.
  15. What is the chemical formula for the cause of Stomache Ulcers?
    Urea + H20 ---UREASE---> Ammonia +CO2
  16. What does urease do in order to allow Helicobacter pylori to colonize?
    Creates ammonia which neutralizes stomache acid in order for Helicobacter Pylori to colonize.
  17. Diffusion of H2O through a semipermeable membrane from higher to lower concentrations until equal
  18. How does a microbe obtain all of its nutrients?
    Through osmotic pressure. They obtain almost all their nutrients in solution from surround water.
  19. Name three tonicities that describe osmotic pressure.
    • Isotonic
    • Hypertonic
    • Hypotonic
  20. What is the most common tonicity for microbial growth?
  21. Review hypertonic, isotonic, and hypotonic solutions
  22. Chemical requirements of bacterial growth can be broke down into two groups. What are they?
    Macro and Micro elements
  23. A microbe has chemical requirements, name 13 of these chemical elements.
    Carbon, Hydrogen, Oxygen, Phosphorus, Potassium, Iodine, Nitrogen, Sulfer, Calcium, Iron, Magnesium, Sodium, Chloride
  24. Bacteria can be classified according to what chemical requirement?
  25. This type of bacteria needs Oxygen for the final receptor of the ETS
  26. This type of bacteria does not need oxygen as a final receptor of the ETS
  27. This type of bacteria can grow with or without oxygen. "Grows Everywhere"
  28. This type of bacteria grows in conditions with small amounts of oxygen present
  29. What two enzymes do Anaerobes lack?
    • Superoxide dismutase
    • Catalase
  30. What does Superoxide do?
    Steals electrons from molecules causing Oxygen to become toxic
  31. What causes Oxygen to be lethal to some organisms?
    All organisms produce superoxide (O2-) which must be neutralized and some organisms can not do this.
  32. What is the chemical formula that creates hydrogen peroxide?
    O2+O2+2H --Superoxide Dismutase--> H2O2 +O2
  33. Why must hydrogen peroxide be neutralized?
    It is lethal to all bacteria.
  34. What enzyme is used to neutralize hydrogen peroxide?
  35. What is the formula to neutralize hydrogen peroxide?
    2H2O2 --Catalase--> 2 H2O+O2
  36. Name two types of culture media
    • Chemically defined Media
    • Complex Media
  37. What is an example of a complex media?
  38. A chemically defined culture is used to grow what type of microbe?
  39. A complex media is used to grow what type of microbe?
    Bacteria and fungi
  40. Is the exact chemical composition known for a chemically defined media?
  41. Is the exact chemical compostition known for a complex media?
  42. Name four special culture techniques for an anaerobe.
    • Reducing media (FTB)
    • Gas Pack
    • Agar stabs
    • Agar shakes
  43. How does FTB work?
    Contains sodium thioglycollate which binds to and removes free oxygen
  44. Name two anaerobic indicators
    Rezasurin, Methalyne blue
  45. Name three parts of a gas pack.
    Rezasurin, Hydrogen Carbondioxide generating envelope, and pallidium crystals
  46. What are normal atmospheric conditions?
    • O2 = 21%
    • CO2 = .3-.03%
  47. What are ideal microaerophilc atmospheric conditions?
    • O2 = 16%
    • CO2 = 4%
  48. What two procedures causes microaerophilic bacteria?
    Candle Jar, Carbon Dioxide generating packet
  49. Name five microaerophilic pathogens and what they cause.
    • Neisseria gonorrheae - gonorrhea
    • Cambylocbacter jejuni - gastroenteritis
    • Barrelia burgdorgeri - lyme disease
    • Helicobacter pylori - stomache ulcers
    • Haemophilis influenzae - meningitis & childhood pnuemonia
  50. This media inhibits  growth for some bacteria while selecting for growth for others
    Selective Media
  51. What type of bacteria is inhibited by dyes?
    Gram (+)
  52. Most gi infections are caused by what type of bacteria?
    Gram (-)
  53. These two types of agar are commonly known for inhibiting bacteria by the use of dye.
    • Brilliant Green Agar
    • EMB (Eosin Methylene Blue)
  54. When using this type of selective media, E.Coli will give off a green metallic color.
    EMB (Eosin Methylene Blue)
  55. What does EMB stand for?
    Eosin Methylene Blue
  56. This type of media differentiates between different organisms growing on the same plate.
    Differential Media
  57. This type of differential media is used to differentiate between different types of streptococci.
    Blood Agar Plate
  58. What is a blood agar plate?
    TSA with 5% sheep blood
  59. Using a blood agar plate, this leaves a incomplete lysis of RBC leaving a yellow-green zone.
    Alpha hemolysis Streptococci
  60. Using a blood agar plate, this leaves a  lysis of RBC leaving a clear zone.
    Beta Hemolytic Streptococci
  61. What is the most common type of streptococci found on a blood agar plate?
    Beta hemolytic streptococci
  62. Using a blood agar plate, this leaves no lysis of RBC leaving no zones.
    Gamma hemolytic streptococci
  63. What does MRSA stand for?
    Methicillin Resistant Staphylococcus aureus
  64. This type of media is used to identify Staphylococcus aureus.
    Mannitol Salt Agar
  65. How does Mannitol Salt Agar inhibit bacteria?
    High salt concentrations (7.5%)
  66. How does Mannitol Salt Agar identify Staphylococcus Aureus?
    Staphylococcus aureus ferments sugar manittol causing a yellow halo (acidic)
  67. What type of media is used to identify Salmonella?
    MacConkeys Agar
  68. What inhibits gram (+) bacteria when using MacConkeys Agar?
    Bile salts and crystal violet
  69. When a MacConkeys Agar is used, how can you identify Salmonella?
    Many non pathogenic gram (-) bacteria can ferment lactose turning the pH indicator red but Salmonella cannot and remains clear.
  70. Increase in the number of cells
    Bacterial growth
  71. Time required for a cell to divide
    Doubling/Generation time
  72. What is E. coli's doubling time?
    20 minutes
  73. What is Mycobacterium tuberculosis's doubling time?
    24 hours
  74. What is the common doubling time for most bacteria?
    1-3 hours
  75. If binary fission is unchecked for a species of E. coli, what is the doubling time for 20 generations in 7 hours?
    1 million cells
  76. If binary fission is unchecked for a species of E. coli, what is the doubling time for 30 generations in 10 hours?
    1 billion cells
  77. If binary fission is unchecked for a species of E. coli, what is the doubling time for 72 generations in 24 hours?
  78. Six limiting factors in the environment that stop bacteria from reaching the reporductive maximum.
    • Lack of food, water, or nutrients
    • space
    • accumulation of metabolic waste
    • lack of oxygen
    • change in pH
    • temperature
  79. Name the 4 phases of growth
    • Lag Phase
    • Log Phase
    • Stationary Phase
    • Death Phase
  80. In the lag phase, bacteria are first introduced into the environment/media. Explain what happens.
    Bacteria check out environment, very active metabolically, number of cells changes very little.
  81. How long does the lag phase last?
    1hr to several days
  82. In the log phase, bacteria rapidly multiplies causing exponintial growth. Explain what happens.
    Population doubles every generation and sensitive to adverse conditions such as antibiotics and antimicrobial agents
  83. In the stationary phase, what happens?
    Death rate is equal to the rate of production, they encounter environmental stress producing endospores
  84. In the death phase, what happens?
    Death rate is greater than rate of reproduction causing the populations to reduce to a tiny fraction or it dies completely
  85. What causes the death rate to be so high in the death phase?
    Limiting factors in the environment
  86. Enumeration of bacteria can be assumed by what process?
    Serial dilution
  87. How many bacterial cells in a turbid culture?
    10 million per mL
  88. In the history between humans and microbes, identify five issues between the two.
    • Infection
    • Disease
    • Plagues
    • Epidemics
    • Pandemics
  89. Continental wide illness
  90. World wide illness
  91. What is another name for the Bubonic Plague?
    Black death
  92. This epidemic swept through Europe in the middle ages
    Bubonic Plague
  93. What centuries did the bubonic plague effect?
    13th and 14th centuries
  94. How many people were killed from the Bubonic Plague? What fraction of the continent was this?
    40 million, approximately 1/3 the continental population
  95. Identify two vectors of the Bubonic Plague
    • Rat
    • Flea
  96. Identify the Etiology Agent of the Bubonic Plague
    Yersinia pestis
  97. Describe the bacteria Yersinia pestis
    Gram (-) bacelli
  98. What is the term describing bacteria in the blood?
  99. Identify the three stages of the bubonic plague infection
    • Flea bites containing Yersenia pestis
    • Bacteria enters the blood stream
    • Bacteria localized in lymph nodes within the axillary and groin regions
  100. Black and blue swelling in the lymph nodes after being infected by the Bubonic Plague
  101. What causes Bubos?
    Hemorrhaging in the lymph nodes
  102. What is the mortality rate of the Bubonic Plague?
  103. What can the Bubonic Plague be called after infecting the lungs?
    Pneumonic Plague
  104. What is the mortality rate of the Pneumonic Plague?
  105. This nursery rhyme refers to the Bubonic Plague
    Ring Around the Rosie
  106. Identify the meaning behind each line of the nursery rhyme that refers to the Bubonic Plague.
    • Ring Around the Rosie - Bubos
    • Pocket Full of Posies- Posies were thought to keep evil spirits away that caused the Bubonic Plague
    • Achoo Achoo - sneezing after the bubos occur
    • We All Fall Down - Death
  107. Where did the saying "I wouldn't touch it with a ten foot pole" come from?
    When the people would move bodies that were infected with the Bubonic Plague they would use a 10 foot pole to avoid being affected.
  108. Throughout history who has been winning the battle between humans and microbes?
  109. In the past 100 years, the battle between microbes and humans has changed. How?
    Humans are taking control of microbial growth.
  110. Where can viles of the Variola virus be found?
    Center of Disease Control
  111. CDC
    Center of Disease Control
  112. USSR
    Institute of virologoy
  113. WHO
    World Health Organization
  114. When and where was the Variola Virus eradicated?
    Somalia in 1977
  115. Small Pox
    Variola Virus
  116. Name two methods of controlling microbial growth.
    • Physical
    • Chemical
  117. Destroying all forms of life
  118. Destroying vegetative pathogens or unwanted organisms
  119. Antimicrobial agent used on inanimate objects
  120. Antimicrobial agent used on live tissues
  121. Kills bacteria
  122. Inhibits bacteria growth
  123. Seven factors that affect antimicrobial activity
    • Temperature
    • Degree of Contamination
    • Time
    • Concentration of antimicrobial agents
    • Sensitivity of the microbe
    • Activity of microbe
    • Organic matter
  124. Name three targets of a antimicrobial agent
    • Cell membrane
    • Enzymes/Proteins (Cell Wall)
    • DNA/RNA
  125. What does heat do to a microbe?
    Denaturizes proteins and enzymes (Cell Wall)
  126. Lowest temperature at which all microorganisms in a liquid culture are killed in 10 minutes
    Thermal Death Point
  127. Minimum length of time in which all microorganisms in a liquid culture are killed at a given temperature.
    Thermal Death Time
  128. Two methods of Moist Heat
    • Boiling water
    • Autoclave
  129. What type of antimicrobial process is boiling water?
  130. What does boiling water kill?
    Vegetative bacterial cells, fungi, and many viruses.
  131. What type of microbes can resist the heat of boiling water?
    Endospores and some Viruses
  132. How long can Hepatitis A last in boiling water? What about it's endospores?
    • 20 minutes
    • 20 hours
  133. What type of antimicrobial process is an autoclave?
  134. What is an autoclave?
    Steam under pressure
  135. What does increased pressure do to boiling water?
    Increases temperature
  136. In an autoclave, if 15 psi is exerted on boiling water, what temperature can be reached?
    121 degrees Celcius
  137. What is the time and temperature required for no known microbe to survive?
    121 degrees Celcius for 15 minutes
  138. What does a Kilit Ampule do?
    Grows Bacillius stearothermophilis
  139. How does a Kilit Ampule work?
    The spores of  Bacillius stearothermophilis are inserted into a kilit ampule along with fermentable sugar incubated at 55 degrees celcius and is watched for fermentation. When fermentation occurs, the pH indicator will change from purple to yellow.
  140. Identify three methods of dry heat
    • Direct flaming
    • Incineration
    • Hot air sterilization
  141. How can direct flaming dry heat be accomplished? What is its effectiveness?
    Innoculating loop and needle, 100% effective
  142. How can incineration dry heat be accomplished?
    Disposable waste is burned to ash.
  143. When is hot air sterilization dry heat necessary?
    When a substance could be damaged by moist heat.
  144. What is hot air sterilization?
    Oven set at 170 degrees celcius for 2 hours.
  145. This method removes microbes from solutions that might be damaged by heat
  146. What is the diameter of each pore of the filtration process? Why is this important?
    .22 u, bacteria is .2-2 u
  147. What is a fault of the filtration method?
    Does not collect all viruses
  148. What can filtration be used for?
    • Culture media
    • Enzymes
    • Vaccines
    • Antibiotics
  149. Name two types of radiation.
    • Ionizing radiation
    • Non Ionizing radiation
  150. What is ionizing radiation?
    Gamma rays and xrays
  151. What type of substances are penetrated by ionizing radiation?
  152. What is ionizing radiation used on? Example?
    • Substances that can be damaged by heat
    • Eg, plastic, catheters, and surgical gloves
  153. What is non ionizing radiation?
    UV light
  154. What is the purpose of non ionizing radiation? Example
    • Reduce microbial population
    • Eg, Hospital rooms, nursery, operating rooms
  155. What is a thymine dimer?
    A bulge in DNA strands from a thick bond
  156. What is pastuerization?
    A disinfectant that removes unwanted organisms.
  157. A microbe that can survive very high temps can be described as what?
  158. HTST
    High temp for short time
  159. What is the temp and time of HTST pastuerization?
    72 degrees celcius for 15 seconds
  160. Before HTST pastuerization what was the ideal temp and time for pasturization?
    63 degrees celcius for 30 minutes
  161. Identify the two types of genetic material
    • DNA
    • RNA
    • Nucleotides
  162. What does DNA stand for?
    Deoxyribose Nucleic Acid
  163. What does RNA stand for?
    Ribonucleic Acid
  164. Identify the three parts of a nucleotide
    • Phosphate group
    • Pentose Sugar
    • Nitrogenous Base
  165. What are the complimentary base pairs of DNA?
    • Adenine - Thyrosine
    • Cytosine - Guanine
  166. In RNA what base is replaced in the complimentary base pairs?
    Thyrosine with Uracil
  167. Identify the proper stucture of DNA
    • Double Helix
    • Polymers of Nucleotids
    • Complimentary Base Pairing
    • Antiparallel (5' - 3')
  168. How many chromosomes does bacteria have? What is it called?
    One. ccDNA
  169. Where does DNA Replication occur?
    At the replication fork
  170. What enzyme connects the okasaki fragments?
    DNA ligase
  171. What are the two strands of the replication fork?
    • Leading Strand
    • Lagging Strand
  172. Which strand of the replication fork continues replication?
    Leading Strand
  173. Which strand of the replication fork discontinues replication?
    Lagging strand
  174. What enzyme begins the replication fork?
    DNA helicase
  175. What enzyme occurs at the leading strand?
    DNA polymerase
  176. What does RNA polymerase do?
    RNA primer
  177. What does DNA polymerase do?
    Extends primer and digests 5' RNA
  178. What three enzymes occur at the Lagging Strand?
    • RNA polymerase
    • DNA polymerase
    • DNA ligase
  179. Explain bidirectional replication.
    the nucleus of a cell is split into two by starting at an origin of replication and going opposite ways until reaching a termination site.
  180. What is another name for protein synthesis?
    Central dogma of molecular genetics
  181. Diagram Protein Synthesis
    DNA ---Transcription---> mRNA ---Translation---> Protein
  182. mRNA
    messenger RNA
  183. What is it called when one strand of DNA is used as a template to form a complimentary strand of mRNA
  184. 3 Ways RNA differs from DNA
    • RNA is single stranded - DNA is double stranded
    • Ribose - Deoxyribose
    • A-U ; C-G | A-T ; C-G
  185. Where the DNA helicase "unzips" the double strand.
  186. What form does the genetic code come for DNA?
    Triplet code
  187. What form does the genetic code come for mRNA?
  188. What form does the genetic code come for tRNA?
    Anti codons
  189. What do codons code for?
    Amino Acid
  190. How many amino acids are there in the human body?
  191. There are three codons that DO NOT code for an amino acid, what are they called?
    Nonsense codons
  192. How many bases per codon?
  193. If there are 3 base codes and 4 bases, how many total codons are there? How many do not code for an amino acid?
    64 possible, 3 do not code for amino acids.
  194. What are codons called that code for amino acids?
    Sense codons
  195. True or False? Amino Acids can be coded for by more than one codon.
  196. Degenerative code can be described as two things. What are they?
    • Degenerative
    • Universal
  197. This codon is a sense codon, its a special codon to start translation.
  198. Three pieces of translation
    • rRNA
    • tRNA
    • anticodon
  199. Three steps of Translation
    • Initiation
    • Elongation
    • Termination
  200. what does rRNA stand for?
    Rhibosomal RNA
  201. what does tRNA stand for?
    Transfer RNA
  202. What is an anticodon?
    three base sequence that is complimentary to the codon on mRNA
  203. This forms 70s rhibosomes when discussing genetics.
  204. This transfer amino acids to rhibosomes for protein synthesis when discussing genetics.