Flashcards in this deck (26)

• What are the three salient features of bacteria?

  • Microorganisms
  • Lack membrane-bound organelles
  • Size: 0.2μm in diameter and 2−8μm in length
  microbiology bacteria
• What are the main groups of bacteria?

  • Gram-positive cocci, bacilli, and branching bacteria
  • Gram-negative cocci, bacilli, and comma-shaped bacteria
  • Spiral-shaped bacteria
  • Acid-fast bacteria
  • Cell-wall-deficient bacteria
  microbiology classification
• What are the nutritional needs for bacterial growth?

  • Cellular constituents: 50%
  • Proteins and nucleic acids: 14%
  • Cellular functions
  microbiology nutrition
• What are the carbon source classifications for bacteria?

  • Require carbon dioxide as sole source
  • Require organic sources from other organisms
  microbiology classification
• What are the energy source classifications for bacteria?

  • Phototrophs
  • Chemotrophs
  microbiology energy
• What is the pH range for most pathogenic bacteria?

  pH 6.0 to 8.0
  microbiology ph
• What temperatures do most bacteria grow at?

  37°C (30 to 37°C)
  microbiology temperature
• What are the oxygen requirement classifications for bacteria?

  • Obligate aerobes
  • Obligate anaerobes
  • Aerotolerant anaerobes
  • Facultative anaerobes
  microbiology oxygen
• What are the four stages of bacterial growth?

  • Lag phase
  • Log phase
  • Stationary phase
  • Death phase
  microbiology growth
• What are the key differences between eukaryotic and prokaryotic cells?

  • Eukaryotes: Mitosis, nuclear body, mitochondria
  • Prokaryotes: Binary fission, nucleoid, energy from cytoplasmic membrane
  microbiology cell_structure
• What are unicellular prokaryotes?

  • Smaller than fungi
  • Bigger than viruses
  • Include spirochetes
  microbiology prokaryotes
• What are the phases of bacterial growth?

  • LAG Phase: Highest metabolic activity
  • LOG Phase: Division rate > Death rate
  • Stationary Phase: Division rate = Death rate
  • DEATH Phase: Division rate < Death rate
  microbiology bacterial_growth
• What are the types of bacteria based on oxygen requirement?

  • Autotrophs: Photosynthesis
  • Heterotrophs: Organic compounds
  • Lithotrophs: Inorganic compounds
  • Organotrophs: Organic compounds
  microbiology bacteria
• What differentiates Gram-positive and Gram-negative bacteria?

  • Gram-positive: Teichoic acids, no outer membrane, susceptible to PCN
  • Gram-negative: No teichoic acids, outer membrane, resistant to PCN
  microbiology gram_staining
• What are the characteristics of exotoxins and endotoxins?

  • Exotoxins: Found in GPB and GNB, heat labile
  • Endotoxins: Found only in GNB, heat stable
  microbiology toxins
• What are cellular appendages in bacteria?

  • Fimbriae: Adherence to host cells
  • Flagella: Motility
  microbiology bacterial_structure
• What are the flagellar arrangements in bacteria?

  • No flagella
  • Flagella at one end
  • Flagella at both ends
  • Single flagellum at both ends
  • Flagella over entire surface
  microbiology flagella
• What is the cellular envelope in Gram-negative bacteria?

  • Initial barrier to environment
  • Primary permeability barriers
  • Contains murein layer for nutrient capture
  microbiology cell_structure
• What is the temperature range for mesophilic bacteria?

  • Optimal temperature: 35°C
  • Tolerate 21% O2
  microbiology temperature
• What are the risk groups for infective microorganisms?

  • Risk Group I: Unlikely to cause disease
  • Moderate Risk: May cause disease but unlikely
  microbiology safety
• What is the risk group for microorganisms unlikely to cause disease?

  Risk Group I
  microbiology risk_groups
• What is the individual risk for Risk Group I microorganisms?

  Unlikely to cause human or animal disease
  microbiology risk_groups
• What is the community risk for Risk Group I microorganisms?

  Unlikely to cause human or animal disease
  microbiology risk_groups
• What is the individual risk for microorganisms in the moderate risk group?

  Moderate Individual Risk
  microbiology risk_groups
• What is the community risk for microorganisms in the moderate risk group?

  Low Community Risk
  microbiology risk_groups
• What can microorganisms in the moderate risk group potentially do?

  May cause disease but unlikely
  microbiology risk_groups