Chapter 6-Test Questions

  1. A microbe recovered from an environmental sample grows on a medium composed of agar and a mix of salts.  This Agar is NOT digested during incubation.  The growth rate increased in HIGH C)2 conditions.  This organism is likely a (n)?
    a) hetertroph
    b) autotroph
    c) chemotroph
    d) halophile
    a) Autotroph
  2. An aquatic microbe that can grow only near the surface of the H2O is probably which of the following?
    a) Phototroph
    b) Heterotroph
    c) Chemotroph
    d) Lithotroph
    a) Phototroph
  3. An Organism that produces CATALASE enzyme is protected from the harmful effects of ______?
    a) singlet Oxygen
    b) hydroxl radical
    c) peroxide anion
    d) superoxide radical
    c) Peroxide anion
  4. Which of the following OXIDIZING agents is sometimes produced during AEROBIC respiration?

    D) Superoxide Radical
  5. A microbe that grows only at the bottom of a tube of Thioglycollate medium is probably a(n)
    Oligate ANAerobe
  6. An Organism that requires Chemical Nutrients which serve as  electron acceptors is a (n)
  7. At temperature higher than the Maxium Growth temp for an organism

    D) Hydrogen bonds broken, Proteins, permanently Denatured, Membranes become too fluid & rigid
  8. Organisms that can grow with/without O2 present are?

    C) Either Faculative ANAerobes or Aerotolerant ANAerobes
  9. Halophiles are found living in HIGH_____
    Salt concentration
  10. A microorganism found living under conditions of HIGH hydrostatic pressure is called a
  11. Microaerophiles are microbes that grow best in low _______.
    Oxygen levels
  12. The _______ growth temp is the temp @ which an organism exhibits the highest growth rate.
  13. You open a jar that has been in the refrigerator for a couple of weeks & find the contents do not look or smell Right.  What type of Microbe has been growing in your refrigerator?
    Psychrophile due to cold temps
  14. Bacteria living in communities of microbes change the genes they are expressing in response to 

    D) Quorum-Sensing Molecules
  15. Microbial growth rates are controlled in a CHEMOSTAT by _________

    B) Controlling the amount of limiting nutrient
  16. MacConkey Agar plates represent _____ medium.

    D) Differential & Selective Medium
  17. A devise that removes wastes & adds fresh Medium to bacterial cultures in order to Prolong the LOG Phase of a culture is called a _____________.
  18. Bacterial BINARY FISSION results in __________ growth.
  19. Which of the Following is an INDIRECT method for estimating the number of microbes in a sample

    A) Turbidity
  20. During which Growth Phase do antimicrobial drugs have the greatest inhibiting effect?

    C) Log phase
  21. Which of the following explains why honey can be stored at room temperature for years without spoiling?
    Osmotic Pressure
  22. The method of obtaining ISOLATED cultures that utilizes surface area to Physically Dilute specimens is called_________.
    Streak-Plate method
  23. All of the Following are part of the Binary Fission EXCEPT????
    Cytoplasmic Membrane production
  24. Which of the Following is an approach to preventing the formation of BIOFILMS?

    A) Increase Quorum Sensing
  25. The_____ method provides an ESTIMATE of the CFU(Colony Forming Units) in a Sample.

    B) Viable Plate-count
  26. Students in a microbiology lab are provided plates of Medium to use in their bacterial culturing.  The growth that can metabolize MANNOSE Sugar will result in the AGAR turning  YELLOW, while the AGAR color remains un-changed if the MANNOSE is NOT Metabolized.  The Plates contain__________Medium.

    C) Differential
  27. Which of the Following Quantification Techniques can distinguish LIVING cells from DEAD Cells in a culture?

    A) Metabolic Activity
  28. The Generation Time of bacterial cells is the SHORTEST during the _______ phase.

    B) Log
  29. When cells are Metabolically active but NOT dividing,they are in the ______phase.

    A) LAG
  30. Metabolic activity is at MAX level in the ___ phase of growth.

    C) LOG
  31. Which of the following Methods is Best for counting Fecal bacteria from a stream to determine the safety of H20 for drinking?

    D) Membrane Filtration
  32. Organisms that Require Organic Sources of Carbon & Energy are called:_______
    Chemo Hetertrophs
  33. Reactions Catalyzed by Superoxide  Dismutases can produce the _____ radical.
  34. A________ can measure changes in the Turbidity of a bacterial culture.

    A) Spectrophotometer
  35. Alkalinophiles can survive in H20 up to pH.

    A) 11.5
  36. A sample placed into fresh medium is initially in the ______ phase of microbial growth in most instances.

    C) Lag
  37. T/F:  Thermoduric Mesophiles are often responsible for spoilage of improperly canned foods.
  38. T/F:  An Obligate ANAerobe can be cultured in a candle jar?
  39. T/F:  Reactions CATALYZED by SUPEROXIDE Dismutases can produce the Peroxide
  40. T/F:  BIOFILMS are the Natural states for the majority of bacteria in Nature.
  41. T/F:  Serial Dilution can be used in combination with Pour Plates as a Method for Isolating Pure cultures?
  42. T/F:  The GENERATION TIME of bacterial culture is determined by the Culture conditions.
  43. Creating conditions in the laboratory that promote the growth of some microbes while inhibiting the growth of others is called

    D) selective enrichment culturing
Card Set
Chapter 6-Test Questions
Microbial Nutrition and Growth