Microbiology 351 Exam 1 Flashcards - Set 5

  1. The bacterial cell wall is made up of ______ interlinked molecule(s).
    a single
  2. The ____ ____ confers shape and rigidity to the cell, and helps it withstand turgor pressure.
    cell wall
  3. Mycoplasma and human cells don't have cell was because the environment is:
    • constant, so there's less risk of osmotic shock.
    • The cell was is expensive to make.
  4. Gram-Positive cell envelope has mutiple layers of _______, and is threaded by ______ _____.
    peptidoglycan, teichoic acids
  5. The Gram-positive capsule is made of ________ and _________.
    polysaccharide, glycoprotein
  6. The bacterial capsule protects cells from _________.
  7. True/False: capsules are also found in Gram-negative cells.
  8. Name the layer in the Gram-Positive Cell Envelope:
    - An additional protective layer commonly found in free-living bacteria and archaea
    - Crystalline layer of thick subunits consisting of protein or glycoprotein
    - May contribute to cell shape and help protect the cell from osmotic stress
  9. Why do Gram-positive cells lose their S-layer after several generations in culture?
    They are in a constant environment and no longer need extra protection. Making the S-layer require a lot of energy & those that don't make it are able to reproduce more.
  10. ___________ have very complex cell envelopes which include unusual membrane lipids (______ ______) and unusual sugars (arabinogalactans).
    Mycobacterial Cell, mycolic acids

    e.g. Mycobacterium tuberculosis & M. Leprae
  11. True/False: The mycolic acid membrane lipids help protect the bacterium from phagocytosis.
    False, this layer allow it to survive in the macrophage though.
  12. Why does a myobacterial cell take a long time to divide?
    It's complex envelope take a lot more energy and time to make.
  13. The Gram-Negative outer membrane consists of a thin peptidoglycan layer of _______ sheets.
    one or two
  14. The Gram-Negative bacteria is covered by an _____ ______, which confers defensive abilities and toxigenic properties on many pathogens, and has _______.
    outer membrane, porins
  15. The Gram-Negative outer membrane's inward-facing leaflet has _______.
  16. The Gram-Negative outer membrane's outward-facing leaflet has ______.
    LPS (Lipopolysaccharides), which can be released into a host's bloodstream and kill them
  17. Algae form cell walls of ______.
  18. Fungi form cell walls of ______.
  19. Diatoms form exoskeletons of ______.
  20. Paramecia possess a ______ ______ to pump water out of the cell.
    contractile vacuole
  21. True/False: Eukaryotic microbes do not possess their own structures to avoid osmotic shock.
  22. True/False: Bacterial cytoskeletons have proteins that determine their shape.
  23. The E. coli nucleoid appears as clear regions that exlcude the _____ and contain the ____ _____.
    ribosomes, DNA strands
  24. The nucleoid form about ___ loops or domains. Within each domain, the DNA is supercoiled by ___-_____ ______.
    50, DNA-binding proteins
  25. Unlike eukaryotes, prokaryotes synthesize RNA and proteins ______ while the cell's DNA undergoes replication.
  26. Bacterial DNA replication is coordinated with the cell wall ______ and ultimately the separation of the two ______ ____.
    expansion, daughter cells
  27. In prokaryotes, a circular chromosome begins to replicate at its orgin, or ____ site.
  28. Prokaryotic DNA replication is bidirectional. At each fork, DNA is synthesized by ___ ______, with the help of accessory proteins (the ______).
    DNA polymerase, replisome
  29. Replication of the termination site triggers growth of the dividing partition, or ______.
  30. The septation of Steptococci are oriented in:
    parallel planes
  31. The septation of Staphylococci are oriented in:
    random planes
  32. The septation of Tatrads and Sarcinae are oriented in:
    perpendicular planes
  33. Bacterial cell poles differ in their origin and "age". This phenomenon is called:
    polar aging
  34. Bacillus species can undergo an _______ cell division to form an endospore at one end.
  35. Some bacteria generate two kinds of daughter cells: one _____ and the other _____.
    stationary, mobile
  36. Named the specialized structure: extensively folded intracellular membranes
  37. Named the specialized structure: polyhedral bodies packed with the enzyme Rubisco for CO2 fixation
  38. Named the specialized structure: increases buoyancy
    gas vesicles
  39. Named the specialized structure: stores Glycogen, PHB, and PHA for energy; sulfur for oxidation
    Storage ganules
  40. Named the specialized structure: Membrane-embedded crystals of megnetie (FE3O4) which orient the swimming of some bacteria

    magnetotactic bacteria
  41. Named the specialized structure: straight filaments of pilin protein, used in attachment, or in conjugation
    pili, or fimbriae
  42. Named the specialized structure: membrane-embedded extensions of the cytoplasm
  43. Named the specialized structure: intercellular connections that pass material from one cell to the next
  44. Prokayotes that are motile generally swim by means of ____ ______.
    rotary flagella
  45. ______ cells have flagella randomly distributed around the cell.
  46. ______ cell have flagella at the end(s)
  47. _____ cells have a single flagellum.
  48. Each flagellum is a spiral filament of protein monomers called ______.
  49. The flagellum is rotated by a motor driven by the _____ ____ ____.
    proton motive force
  50. ________ rotation of the flagella moves the cell towards the attractant.
  51. ______ rotation of the flagella stops forward motion, so cell tumbles and changes direction.
  52. Most bacteria divide by _____ fission.
  53. ____ and ____ are used for attachment.
    Pili, stalks
  54. ______ are rotary appendages used for movement and chemotaxis
  55. In fluorescence microscopy, the specimen absorbs light and then re-emits it at a ____ energy and thus, a _____ wavelength.

    C) lower; longer
  56. All of the following are used to lyse cells EXCEPT:

    E) Electrophoresis
  57. Which of the following statements about membrane lipids is true?

    B) Lipids of bacteria have ester linkages, while those of archaea have ether linkages.
Card Set
Microbiology 351 Exam 1 Flashcards - Set 5
Cell Structure and Function II