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6. The extracellular polysacharide matrix surrounding the microorganisms in the biofilm do what?

  • Protect from disinfectant, provides nutrients, forms network for host tissue damage
  • Provide protection from disenfectant, provide nurtients, provide reservoir for gene transfer and qourum sensing
  • Provide reservoir for gene transfer by providing plasmids
  • Provides nutrients and oxygen for aerobic microorganisms

7. Formation of a biofilm in an industry depends on..

  • Food matrix, cleaning policies, open surfaces, location
  • Food matrix, employee numbers, age of employees
  • Cleaning products used, cleaning rota

8. When grown with Pseudamonas, Monocytogenes adhered to a glass surface, ______ than when alone

  • Better
  • Worse

9. the four steps in biofilm establishment are...

  • conditioning, attachment, retention, metabolism
  • conditioning, adhesion, metablosim, survival
  • conditioning, attachment, gene transfer, metabolism

10. Which of the following is a common place for biofilm formation and may provide nutrients

  • catheters
  • aluminum
  • stainless steel
  • copper

11. Which can remove a biofilm after the bacteria complexes with a surface?

  • rinsing
  • scraping, scrubbing, chemicals
  • chemicals and rinsing
  • boiling water and scrubbing

12. The environment of a biofilm is described as mostly ______ for the microorganisms involved

  • synergistic
  • beneficial
  • disadvantageous

13. The presence of albumin ________ the attachment of Pseudomonas to polystyrene

  • promotes
  • has no effect
  • inhibits
  • aids

14. Bacterial interaction with a surface relies on

  • flagella and fimbrae
  • flagella activiy and chemotaxis
  • chemotaxis and competition

15. Define a biofilm

  • When one microorganism colonises a tissue and releases endotoxins
  • A community of pathogens adhered to a host cell
  • A large number of pathogens which use quorum sensing to adhere to a surface, encase in a polymeric matrix
  • A community of microoganisms adhered to a surface encased in an extracellular polymeric substance
  • A community of pathogens co-aggregated to a host encase in an extracellular polymeric substance

16. What may be competition for binding sites in biofilm adhesion?

  • Proteins
  • Inflammatory cells
  • Other microorganisms
  • Host tissue

17. Co-aggregation is..

  • when the host's immune response ruptures the biofilm
  • when the microorganisms stick to the surface
  • when two species of micoorganisms adhere to eachother
  • when the biofilm is disrupted by multiple things

18. the use of broad spectrum antibiotics leads to...

  • penetration of top layer
  • all of the answers are correct
  • resitance
  • gene transfer

19. Dairy food industry harbours which kind of microorganisms

  • thermophiles and streptococci
  • thermophiles and candida
  • hydrophiles and staphylococcus
  • candida and steptococci

20. Biofilms form...

  • gradually
  • in the presence of calcium
  • when host immunity is low
  • rapidly