Microbiology 351 Exam 1 Flashcards - Set 9

  1. Name the type of microbial nutrition:
    - must be supplied from the envrionment
    Essential nutrients
  2. Name the type of microbial nutrition:
    - Major elements in the cell macromolecules
      - C, H, O, N, P, S
    - Ions necessary for protein function
      - Mg2+, Ca2+, Fe2+, K+
  3. Name the type of microbial nutrition:
    - Trace elements necessary for enzyme function
      - Co1+, Cu2+, Mn2+, Zn2+
  4. Based on its niche, an organism may have evolved to require additional ____ _____.
    - specific nutrients not required by all cells (NAD, amino acids, vitamin K, etc.)
    growth factors
  5. A _____ _____ _____ contains only the compounds needed for an organism to grow
    defined minimal medium
  6. For many microorganisms, we do not know what is required for growth __ _____.
    in vitro
  7. All of Earth's life-forms are based on _____, which they acquire in different ways.
    - _____ use preformed organic molecules
    - _____ fix CO2 and assemble into organic molecules (mainly sugars)
    • carbon
    • - heterotrophs
    • - autotrophs
  8. All organisms require an energy source.
    - _____ obtain energy from chemical reactions triggered by light.
    - _____ obtain energy from oxidation-reduction reactions
    • phototrophs
    • chemotrophs
  9. Organisms differ in source of electrons.
    - _____ use inorganic molecules.
    - _____ use organic molecules
    • lithotrophs
    • organotrophs
  10. N2 is ____% of the atmosphere but is unavailable for use by most organisms.
  11. Nitrogen ______ possess notrogenase, which converts N2 to ______ ____.
    • fixers
    • ammonium ions (NH4+)
  12. ______ oxidize ammonia to nitrate (NO3-)
  13. _____ convert nitrate to N2.
  14. ______ are symbionts in leguminous plants such as soybeans, chickpeas, and clover
  15. A membrane potential is generated when ______ energy is used to pump protons outside of the cell.
  16. The H+ gradient plus the charge difference from an electrochemical potential is called the ____ ____ ____.
    proton motive force
  17. The potential energy stored through the membrane potential can be used to transport nutrients, drive flagellar rotation and make ATP by the ____ ____ _____.
    F1F0 ATP synthase
  18. Selective permeability is achieved in three ways:
    - Substrate-specific carrier proteins called ______
    - Dedicated nutrient-binding proteins that patrol the ______ space
    - Membrane spanning protein _____ or _____
    • - permeases
    • - periplasmic
    • - channels, pores
  19. ______ _____ helps solutes move across a membrane from high to low concentration.
    - It does not use energy and cannot move a molecule against its gradient
    Facilitated diffusion
  20. Aquaporin family transports ______.
  21. _____ ____ _____ are those in which energy released by moving a driving ion down its gradient is used to move a solute up its gradient.
    - active transport
    Coupled transport systems
  22. Name the type of transport across the membrane:
    - the two molecules travel in the same direction
  23. Name the type of transport across the membrane:
    - the actively transported molecule moves in the direction opposite to the driving ion
  24. The largest family of energy-driven transport systems is the ___-____ _____ superfamily.
    - they are found in all three domains of life
    ATP-binding cassette (or ABC transporters)
  25. Name the type of ATP-binding cassettes (or ABC transporters):
    - critical for transporting nutrients
  26. Name the type of ATP-binding cassettes (or ABC transporters):
    - generally used as multidrug efflux pumps
    - can pump antibiotics our of the cell & make cell resistant
  27. ______ are specialized molecules secreted to bind ferric ion (Fe3+) and transport it into the cell.
    - the iron is released into the cytoplasm and reduced to the more useful ferrous (Fe2+) form
  28. Neisseria gonorrhoeae employs receptors onits surface that bind human ____ complexes and wrest the ____ from them.
    iron, iron
  29. ____ _____ is a process that uses energy to chemically alter the substrate during its transport.
    Group translocation
  30. The _______ _____ is an example of group translocation that is present in all bacteria.
    - it uses energy from phosphoenolpyruvate (PEP) to attach a phosphate to specific sugars.
    - the system has a modular design that accommodates different substrates
    Phosphotransferase system (PTS)
  31. Microbes in nature exist in complex, multispecies communities, but for detailed studies they must be grown separately in ____ _____.
    pure culture
  32. We have succeeded in culturing only ____% of the microorganisms around us.
  33. Bacteria are grown in culture media, which are of two main types: _____ (_____) or _____ (usually ____)
    liquid (broth), solid (usually agar)
  34. Pure colonies are isolated via _____ or _____ plate.
    streaking, spread
  35. ____ of living and dead cells can be done using:
    - Optical Density (OD)
    - Fluorescence-Activated Cell Sorter (FACS)
    - Pour plate: view colony forming unit (CFU)
    - indirectly (cell mass, protein content or metabolic rate)
  36. The ____ ____, or rate of increase in cell numbers of biomass, is proportional to the population size at a given time.
    growth rate
  37. _____ ____ is the time it takes for a population to double.
    Generation time
  38. If a cell divides by _____ _____, the number of cells is proportional to 2n (n = number of generations)
    binary fission
  39. Binary fission is called _____ because it generates an ______ curve, a curve whose slope increases continually.
    exponential, exponential
  40. True/False: Exponential growth lasts indefinitely.
    False, it never does.
  41. The simplest way to model the effects of a changing environment is to culture bacteria in a _____ culture (liquid medium within a closed system).
  42. The changing conditions in a batch culture system greatly affect bacterial ______ and _____.
    physiology, growth
  43. In a ______ culture, all cells in a population achieve a steady state, which allows detailed study of bacterial physiology.
  44. The ____ ensures logarithmic growth by constantly adding and removing equal amounts of culture media.
    • chemostat
    • (human GI tract ~ chemostat)
  45. Many bacteria form specialized, surface-attached community called _____.
    - one or multiple species, organic or inorganic surfaces
    - form when nutrients are plentiful
    - once nutrients become scare, individuals detach from the community to forage for new sources of nutrients
  46. Microbes require certain essential _____ and ______ to grow.
    macronutrients, micronutrients
  47. Microbes are classified on the basis of their ____ and ____ acquisition.
    carbon, energy
  48. _____ transport does not require energy.
    - simple and facilitated diffusion
  49. ____ transport required energy
    - coupled transport
    - ABC transporters
    - Group translocation
  50. The growth cycle of organisms grown in liquid batch culture consists of four phases:
    • 1. Lag
    • 2. Logarithmic
    • 3. Stationary
    • 4. Death
  51. Viriods are _____ agents that infect _____.

    C) RNA; plants
  52. What do all viruses contain?

    B) a capsid and a genome
  53. The Baltimore system classifies viruses based predominantly on

    C) Their means of mRNA synthesis
Card Set
Microbiology 351 Exam 1 Flashcards - Set 9
Bacterial Growth