14-25

• What is the qualitative chemical composition of bacteria similar to?

  Animal and plant cells
• What percentage of total cell mass does water constitute in bacteria?

  80-85%
• What role does water play in bacterial cells?

  Solvent, medium for electrolyte dissociation
• What happens to bacteria when water content decreases?

  Replication stops or cell death occurs
• What methods are used for food and strain preservation by reducing water content?

  Drying and lyophilization
• What percentage of dry substance constitutes the cell mass of bacteria?

  2-25%
• What minerals are included in the dry substance of bacteria?

  K, N, P, C, S, Mg, Fe
• Why is phosphorus crucial for bacteria?

  It is essential for nucleic acids and enzymes
• What role does sulfur play in bacterial cells?

  Found in amino acids and biological oxidation
• What is the largest portion of dry substance in bacteria?

  Proteins
• What are the two types of proteins found in bacteria?

  Simple and complex proteins
• What do nucleic acids in bacteria include?

  RNA and DNA
• What percentage of dry substance do carbohydrates constitute in bacteria?

  12-28%
• What are the functions of carbohydrates in bacteria?

  Cell envelope components and nutrient reserves
• What is the role of lipids in bacterial cells?

  Cell envelope structure and nutrient reserves
• What is the optimal pH for most bacteria growth?

  7.2-7.4
• What is the NaCl concentration necessary for normal nutrient transport in bacteria?

  0.5-0.8%
• What are growth factors in bacterial cultivation?

  Specific small-amount requirements for metabolism
• What is the optimal temperature for most pathogenic bacteria?

  35-37°C
• How are bacteria classified based on oxygen requirements?

  Obligate aerobes, anaerobes, facultative anaerobes
• What are the types of artificial media based on composition?

  Minimal essential, complex, selective, differential
• What is the purpose of selective media?

  Promote specific bacterial growth while inhibiting others
• What is the physical state of media used in bacterial cultivation?

  Broth, semi-solid, solid
• How do bacteria absorb nutrients?

  Through their entire surface
• What is the process of nutrient acquisition in bacteria?

  Hydrolysis of macromolecules by exocellular enzymes
• What is the common intermediate produced from metabolites in bacteria?

  Pyruvic acid
• What are the two main processes of bacterial metabolism?

  Anabolic and catabolic processes
• What is the primary method of energy production in bacteria?

  Fermentative and respiratory metabolic pathways
• What is the major glucose utilization pathway in bacteria?

  The glycolytic (Embden-Meyerhof) pathway
• What is produced during Phase I glycolysis?

  ATP and reduced NAD (NADH)
• What happens during Phase II glycolysis in the absence of oxygen?

  Pyruvate is converted to different end products
• What is the function of virulence factors in pathogenic bacteria?

  Facilitate invasion and tissue dissemination
• What is the yield of ATP from complete respiration in bacteria?

  38 molecules of ATP per glucose
• What are growth factors in bacterial metabolism?

  Substances required in small amounts
• What are bacterial enzymes classified by?

  Type of biochemical reactions and localization
• What is the role of exocellular enzymes in bacteria?

  Convert large macromolecules into smaller ones
• What is the average generation time for bacterial cell division?

  Around 20 minutes
• What is the bacterial growth cycle characterized by?

  Four distinct phases in a closed system
• What occurs during the lag phase of bacterial growth?

  Physiological adjustment to new conditions
• What characterizes the logarithmic phase of bacterial growth?

  Maximal rates of cell division