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• What do microbes need as a source of energy and carbon?

  Source of energy and carbon
• What are macronutrients required by microbes?

  C, O, H, N, P, S in large amounts
• What are micronutrients for microbes?

  Minerals and trace elements
• What is the role of chemoorganotrophic microbes?

  They oxidize organic and inorganic materials
• What do photoautotrophic microbes utilize?

  Solar energy
• What is the macromolecular composition of E. coli?

  • Protein: 55%
  • Lipid: 9%
  • Polysaccharides: 6%
  • DNA: 3.1%
  • RNA: 20.5%
• What trace element is essential for bacterial quorum sensing?

  Boron (B)
• What is the function of cobalt (Co) in microbes?


  It is part of vitamin B12
• What role does copper (Cu) play in microorganisms?


  For respiration and photosynthesis
• What is the function of iron (Fe) in microbes?


  It is used in cytochromes and catalase
• What is manganese (Mn) used for in microorganisms?


  Component of superoxide dismutase
• What is the role of molybdenum (Mo) in microbes?


  It is part of nitrogenase and nitrate reductase
• What is the function of selenium (Se) in microorganisms?


  It is part of vitamin E
• What is the role of zinc (Zn) in microbes?


  It is used in DNA polymerase
• What are the growth factors required by microorganisms?

  • PABA (p-aminobenzoic acid)
  • Thiamin (B1)
  • Biotin (B7)
  • Folic acid
  • Riboflavin (B2)
  • Niacin (B3)
  • Pantothenic acid (B5)
  • Pyridoxine (B6)
  • Vitamin C
  • Vitamin K
  • Vitamin B12
• What are the two types of culture media?

  Defined media and complex media
• What is defined media?

  Precise amounts of purified chemicals
• What is complex media?

  Digests products of nutrients in unknown amounts
• What is binary fission?

  Cell division resulting in two cells
• What is generation time (g)?

  Time for a cell to divide into two
• What is the minimum generation time for microbial growth?

  30 minutes
• What is the maximum generation time for microbial growth?

  1000 minutes
• What does transpeptidation inhibition lead to?

  Leads to lysis of bacterial cells
• What does penicillin inhibit?

  Inhibits transpeptidation in bacteria
• What are the types of microbial growth?

  • Binary fission
  • Budding from hyphae
  • Polar growth
  • Simple budding
  • Stalked bacteria
  • Planktonic growth
  • Biofilm growth
• What is planktonic growth?

  Growth suspended in a system
• What is biofilm growth?

  Growth attached to a surface in a matrix
• What are the stages of biofilm development?

  1. Attachment of planktonic cells
  2. Production of sticky matrix
  3. Surface growth and development
• What is population growth in microbes?

  Increase in the number of cells
• What is exponential growth in microbial populations?

  One cell becomes two in division
• What is the characteristic of a continuous culture device?

  Population density controlled by nutrients
• What are the methods for measuring microbial growth?

  • Microscopic cell counts
  • Viable counts
  • Turbidimetric measures
• What environmental factors affect microbial growth?

  Temperature, acidity, osmotic effects, oxygen