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Microbiology Exam 2

71 Questions
Microbiology Quizzes & Trivia

Exam 2 for Microbiology 130

Questions and Answers
  • 1. 
    Which nutritional requirement is “iron (Fe2+)†considered to be a part of?
    • A. 

      The major nutritional elements

    • B. 

      Trace elements

    • C. 

      Organic growth factors

    • D. 

      Vitamins

  • 2. 
    Cells that live in high salt environments are called ________.
    • A. 

      Plasmophiles

    • B. 

      Saltophiles

    • C. 

      Tonophiles

    • D. 

      Halophiles

  • 3. 
    • A. 

      30

    • B. 

      37

    • C. 

      45

    • D. 

      60

  • 4. 
    • A. 

      0

    • B. 

      10

    • C. 

      37

    • D. 

      45

  • 5. 
    Which of these is a good method of preserving microbial cultures?
    • A. 

      Lyophilization

    • B. 

      Heating

    • C. 

      Salting

    • D. 

      Pickling

  • 6. 
    • A. 

      Obligate aerobe

    • B. 

      Facultative aerobe

    • C. 

      Obligate anaerobe

    • D. 

      Aerotolerant anaerobe

  • 7. 
    Mannitol salt agar contains 7.5% salt which only allows the growth of microbes associated with the human body, such as Staphylococcus species. Furthermore, those that are able to ferment mannitol appear yellow in color. What type of medium is Mannitol salt agar?
    • A. 

      Selective

    • B. 

      Differential

    • C. 

      Selective and Differential

    • D. 

      Enrichment

  • 8. 
    • A. 

      True

    • B. 

      False

  • 9. 
    Which of these microbes is most problematic to humans?
    • A. 

      Psychrophile

    • B. 

      Psychrotroph

    • C. 

      Mesophile

    • D. 

      Thermophile

  • 10. 
    Salts and sugars work to preserve foods by creating a ____.
    • A. 

      Lower osmotic pressure

    • B. 

      Hypotonic environment

    • C. 

      Lower pH

    • D. 

      Hypertonic environment

  • 11. 
    The large intestines is an environment that lacks any oxygen. Which of the following types of organisms would most likely be found there?
    • A. 

      Obligate aerobe

    • B. 

      Obligate anaerobe

    • C. 

      Microaerophile

    • D. 

      Aerotolerant anaerobe

  • 12. 
    • A. 

      Lag

    • B. 

      Log

    • C. 

      Stationary

    • D. 

      Death

  • 13. 
    Which of these microbes is most likely to grow at room temperature (25 C)?
    • A. 

      Psychrophile

    • B. 

      Psychrotroph

    • C. 

      Thermophile

    • D. 

      Hyperthermophile

  • 14. 
    ____ is used if you want to study obligate anaerobic microbes.
    • A. 

      Enrichment media

    • B. 

      Selective media

    • C. 

      Reducing media

    • D. 

      Differential media

  • 15. 
    You want to quantify a culture of motile bacteria. Which method of quantifying would you use if you needed the most accurate information as soon as possible?
    • A. 

      Plate count

    • B. 

      MPN

    • C. 

      Turbidity

    • D. 

      Microscopic count

    • E. 

      Dry weight

  • 16. 
    Motility medium is a growth agar medium that contains a low agar concentration. Cells that are motile will be able to grow throughout the medium whereas non-motile cells will only grow where they were inoculated. What type of medium is motility medium.
    • A. 

      Differential

    • B. 

      Selective

    • C. 

      Differential and selective

    • D. 

      Enrichment

  • 17. 
    Which of these organisms would not be able to grow in water that has oxygen pumped into it (aerated)?
    • A. 

      Obligate aerobe

    • B. 

      Facultative aerobe

    • C. 

      Obligate anaerobe

    • D. 

      Aerotolerant anaerobe

  • 18. 
    Most human pathogens are _________.
    • A. 

      Psychrophiles

    • B. 

      Mesophiles

    • C. 

      Thermophiles

    • D. 

      Psychrotrophs

  • 19. 
    Which method of quantifying bacterial numbers would be most effective for measuring the numbers of bacteria in drinking water, when you expect the numbers to be relatively low?
    • A. 

      Filtration

    • B. 

      Plate count

    • C. 

      Direct microscopic count

    • D. 

      Turbidity

  • 20. 
    Which of the following is a limitation of the autoclave?
    • A. 

      Requires a long time to achieve sterilization.

    • B. 

      Cannot inactivate viruses.

    • C. 

      Cannot kill endospores.

    • D. 

      Cannot be used with heat-sensitive materials.

  • 21. 
    • A. 

      Ionizing radiation

    • B. 

      Autoclaving

    • C. 

      0.45 um filtration

    • D. 

      Gamma radiation

  • 22. 
    A microbial culture contains 1 million cells. If it takes 25 minutes to kill all microbes in a culture, the DRT is ______.
    • A. 

      25 minutes

    • B. 

      1 million cells

    • C. 

      Not enough information

  • 23. 
    Which one of the following would be the most likely to spoil a jar of jam in your fridge?
    • A. 

      Eurotium, a mold

    • B. 

      Pseudomonas, a psychrotrophic bacterium

    • C. 

      Thibacillus, an acidophile

    • D. 

      Streptococcus pyogenes, a human pathogen

  • 24. 
    Based upon the information provided, which of these disinfectant treatments is more effective, a higher concentration for a shorter time, or a lower concentration for a longer time?
    • A. 

      High concentration, short time.

    • B. 

      Low concentration, long time.

    • C. 

      Equally effective.

  • 25. 
    In the disk-diffusion method, a ____ zone of inhibition around a filter soaked with a chemical indicates that the test bacteria is resistant to the chemical.
    • A. 

      Small

    • B. 

      Large

    • C. 

      Colored

    • D. 

      Clear

  • 26. 
    Which of the following is not used to preserve foods?
    • A. 

      Desiccation

    • B. 

      Ionizing radiation

    • C. 

      Microwaves

    • D. 

      Osmotic pressure

  • 27. 
    Which of these are most likely to survive in a hypertonic environment?
    • A. 

      Bacteria

    • B. 

      Molds

    • C. 

      Viruses

    • D. 

      Algae

  • 28. 
    Pseudomonas species are unusually resistant to antimicrobial treatment due to the presence of _________.
    • A. 

      Porins

    • B. 

      A plasma membrane

    • C. 

      An extremely hard cell wall

    • D. 

      Antibiotics

  • 29. 
    Which of these have a direct effect on antimicrobial treatments?
    • A. 

      Climate

    • B. 

      Mass of surface being treated.

    • C. 

      Number of microbes present.

    • D. 

      Area of surface being treated.

  • 30. 
    All media needs to be free of microbes, so you need to ____ media before you use it.
    • A. 

      Sterilize

    • B. 

      Disinfect

    • C. 

      Sanitize

    • D. 

      Degerm

  • 31. 
    Bacterial death will result from damage to which of the following structures?
    • A. 

      Plasma membrane

    • B. 

      Proteins

    • C. 

      Nucleic acids

    • D. 

      All of the above

  • 32. 
    Salts and sugars work to preserve foods by creating a ____.
    • A. 

      Lower osmotic pressure

    • B. 

      Hypotonic environment

    • C. 

      Lower pH

    • D. 

      Hypertonic environment

  • 33. 
    A bacterial culture was treated at 55 C. Treating the culture for 5 and 10 minutes did not effectively kill the bacteria, but treatment for 15 minutes killed all the cells. What is the TDT?
    • A. 

      5 mins

    • B. 

      10 mins

    • C. 

      15 mins

    • D. 

      More than 15 mins

  • 34. 
    A microbial culture contains 1 million cells. If it takes 25 minutes to kill all microbes in a culture, the TDT is ______.
    • A. 

      25 minutes

    • B. 

      1 million cells

    • C. 

      Not enough information

  • 35. 
    Commercial sterilization involves heat treatment to destroy ______ of bacteria.
    • A. 

      The plasma membrane

    • B. 

      Peptidoglycan

    • C. 

      Endospores

    • D. 

      The outer membrane

  • 36. 
    TRNA molecules serve as a link between ______.
    • A. 

      DNA and mRNA

    • B. 

      Codons and anticodons

    • C. 

      Codons and amino acids

    • D. 

      MRNA and rRNA

  • 37. 
    A gene is best defined as ______.
    • A. 

      A segment of DNA

    • B. 

      Three nucleotides that code for an amino acid

    • C. 

      A segment of DNA that codes for a functional product

    • D. 

      A segment of RNA that codes for a functional product

  • 38. 
    The LacI repressor of the lac operon binds to the ______ when lactose is not present.
    • A. 

      Promoter

    • B. 

      Operator

    • C. 

      Inducer

    • D. 

      Regulator

  • 39. 
    Which of these anticodons are found on the tRNA molecule for the amino acid methionine?
    • A. 

      UAC

    • B. 

      AUG

    • C. 

      ATG

    • D. 

      CUG

  • 40. 
    Which of these is involved in translation?
    • A. 

      DNA polymerase

    • B. 

      RNA polymerase

    • C. 

      DNA

    • D. 

      MRNA

  • 41. 
    The information carried by DNA is used to create a _____ which then moves to the ribosome for protein synthesis.
    • A. 

      TRNA

    • B. 

      RRNA

    • C. 

      MRNA

    • D. 

      DRNA

  • 42. 
    Which of the following properties are exclusive (unique) to mRNA?
    • A. 

      Combines with specific proteins to form ribosomes.

    • B. 

      Carries information from DNA for synthesis of a protein.

    • C. 

      Molecules contain an anticodon.

    • D. 

      Contains the nucleotide thymine.

  • 43. 
    E. coli can metabolize both glucose and lactose. If grown in the presence of both sugars, E. coli will metabolize glucose first. This is referred to as _______.
    • A. 

      Catabolite repression

    • B. 

      Catabolite induction

    • C. 

      Inducible expression

    • D. 

      Repressible expression

  • 44. 
    The enzyme responsible for transcription is
    • A. 

      DNA polymerase

    • B. 

      RNA polymerase

    • C. 

      Ribosomes

    • D. 

      Transposase

  • 45. 
    Which of the following properties are exclusive (unique) to rRNA?
    • A. 

      Combines with specific proteins to form ribosomes.

    • B. 

      Carries information from DNA for synthesis of a protein.

    • C. 

      Molecules contain an anticodon.

    • D. 

      Contains the nucleotide thymine.

  • 46. 
    The three nucleotide units in an mRNA molecule that code for amino acids are called ______.
    • A. 

      Proteins

    • B. 

      Genes

    • C. 

      RRNA

    • D. 

      Codons

  • 47. 
    Which of the following properties are exclusive (unique) to tRNA?
    • A. 

      Combines with specific proteins to form ribosomes.

    • B. 

      Carries information from DNA for synthesis of a protein.

    • C. 

      Molecules contain an anticodon.

    • D. 

      Contains the nucleotide thymine.

  • 48. 
    A sequence of DNA nucleotides which provides genetic information for a functional product is a ______.
    • A. 

      Chromosome

    • B. 

      Plasmid

    • C. 

      Gene

    • D. 

      Base pair

  • 49. 
    Which enzyme is responsible for unzipping the double stranded DNA?
    • A. 

      DNA polymerase

    • B. 

      DNA helicase

    • C. 

      DNA ligase

    • D. 

      DNA zippase

  • 50. 
    Phosphoglycerate kinase (PGK), an enzyme involved in glycolysis, is constitutively expressed. Which statement is true about the PGK gene?
    • A. 

      PGK is expressed when glucose is present.

    • B. 

      PGK is always expressed.

    • C. 

      The expression of PGK is repressed when glucose is present.

    • D. 

      You cannot predict the pattern of PGK expression.

  • 51. 
    An anticodon would be found in/on a _____ molecule.
    • A. 

      MRNA

    • B. 

      TRNA

    • C. 

      Gene

    • D. 

      RRNA

  • 52. 
    Which of the following is not a disadvantage of E. coli for making a human gene product?
    • A. 

      Endotoxin may be in the product.

    • B. 

      It doesn't secrete most proteins.

    • C. 

      Its genes are well known.

    • D. 

      It grows very slow.

  • 53. 
    A technique used to identify bacteria carrying a specific gene is ______.
    • A. 

      Southern blot

    • B. 

      Shotgun sequencing

    • C. 

      Transformation

    • D. 

      Cloning

  • 54. 
    Two daughter cells are most likely to inherit which one of the following from the parent cell?
    • A. 

      A change in a nucleotide in mRNA.

    • B. 

      A change in a nucleotide in tRNA.

    • C. 

      A change in a nucleotide in rRNA.

    • D. 

      A change in a nucelotide in DNA.

    • E. 

      A change in a protein.

  • 55. 
    A ______ is able to transfer antibiotic resistance to other bacteria via conjugation.
    • A. 

      F factor

    • B. 

      R factor

    • C. 

      Transposon

    • D. 

      Bacteriophage

  • 56. 
    In transformation, the recipient cell is a _____.
    • A. 

      Viral infected cell

    • B. 

      Competent cell

    • C. 

      Cell without a plasmid

    • D. 

      Bacteriophage

  • 57. 
    How does a shuttle vector differ from a "regular" plasmid vector? Shuttle vectors _____.
    • A. 

      Are self replicating

    • B. 

      Can exist in both eukaryotes and prokaryotes

    • C. 

      Are cicrular

    • D. 

      Can only carry antibiotic resitance genes

  • 58. 
    A typical transposon is flanked by _____.
    • A. 

      Resistance factors

    • B. 

      Inverted repeats

    • C. 

      RTF genes

    • D. 

      Repressor sites

  • 59. 
    What is the primary purpose of PCR?
    • A. 

      To make a segment of DNA larger.

    • B. 

      To transcribe a segment of DNA.

    • C. 

      To replicate a segment of DNA.

    • D. 

      To move a piece of DNA from one cell to another.

  • 60. 
    The genetic information needed for a F+ cell to participate in conjugation can be found in the DNA of a cell's ____.
    • A. 

      Chromosome

    • B. 

      F factor

    • C. 

      F pilus

    • D. 

      Mitochondria

  • 61. 
    An advantage of a subunit vaccine is that subunit vaccines _______.
    • A. 

      Consist of plasmid DNA

    • B. 

      Are much more efficient than regular vaccines

    • C. 

      Have no chance of infecting patients

    • D. 

      Can turn off viral genes

  • 62. 
    Gene therapy would describe which of the following scenarios?
    • A. 

      Bacteria which produce human growth hormone.

    • B. 

      A DNA comparison in a paternity case.

    • C. 

      Yeast which has been genetically engineered to produce yeast from starch.

    • D. 

      Replacing a defective gene in human cells.

  • 63. 
    Hfr cells arise when _____.
    • A. 

      They have multiple F plasmids

    • B. 

      A cell's F plasmid has been incorporated into the bacterial chromosome

    • C. 

      Conjugation and transformation happen at the same time

    • D. 

      Bacterial chromosomes do not break during conjugation

  • 64. 
    Bioinformatics is the field of study that employs computers to understand ______.
    • A. 

      The protein expression in a cell.

    • B. 

      How recombinant DNA is generated.

    • C. 

      How DNA is replicated.

    • D. 

      How genes are organized

  • 65. 
    _______ is gene transfer mediated by bacteriophages.
    • A. 

      Transformation

    • B. 

      Conjugation

    • C. 

      Transduction

  • 66. 
    In transduction, the donor cell could be _____.
    • A. 

      A cell that had died and burst

    • B. 

      A cell that carries a plasmid

    • C. 

      A cell that has been infected with a virus

    • D. 

      A cell that has a transposon

  • 67. 
    An auxotroph can best be described as _______.
    • A. 

      A microbe that has a nutritional deficiency

    • B. 

      A microbe that has no nutrional deficiencies

    • C. 

      A microbe that has one nutrional deficiency

    • D. 

      A microbe that has a nutritional deficiency relative to its parent

  • 68. 
    Electroporation is a technique that is used to _____.
    • A. 

      Kill bacteria

    • B. 

      Introduce DNA into bacterial cells

    • C. 

      Increase conjugation among bacteria

    • D. 

      Increase the transduction efficiency of bacteria

  • 69. 
    In conjugation, the donor cell could be ______.
    • A. 

      A cell that had died and burst

    • B. 

      A cell that carries a plasmid

    • C. 

      A cell that has been infected with a virus

    • D. 

      A cell that has a transposon

  • 70. 
    Which of the following is not a method of horizontal gene transfer?
    • A. 

      Binary fission

    • B. 

      Conjugation

    • C. 

      Integration of a transposon

    • D. 

      Transfer of DNA via a bacteriophage infection

    • E. 

      Uptake of DNA from the environment

  • 71. 
    Which method of microbial control aims to destroy all microbes?
    • A. 

      Disinfection

    • B. 

      Sterilization

    • C. 

      Commercial sterilization

    • D. 

      Sanitization