Bacterial nutrition

• What are the main outlines covered in the study material on bacterial nutrition?

  • Introduction to bacterial nutrition
  • Classification based on mode of nutrition
  • Carbon requirements
  • Energy requirements
  • Electron source
  • Bacterial growth
• What is required by all living things, including bacteria?

  Nutrition
• Why do bacteria require energy and nutrients?

  To build proteins, structural membranes, and drive biochemical processes
• What factors affect bacterial growth?

  Nutritional requirements are one of the factors affecting bacterial growth
• What are the primary elements required by bacteria in large quantities?

  Carbon, nitrogen, and water
• What are micronutrients required by bacteria?

  Elements like zinc, copper, manganese, selenium, tungsten, and molybdenum
• What is the most required element by bacteria?

  Carbon
• What is a prerequisite for bacterial growth?

  Water
• How can bacteria be classified based on their nutritional needs?

  Based on carbon source and energy source
• What are the two sources a cell can use for carbon?

  Inorganic compounds and organic compounds
• What are autotrophs?

  Organisms that use inorganic carbon dioxide (CO₂) as their source of carbon
• What are heterotrophs?

  Bacteria that require an organic source of carbon, such as sugars or proteins
• Give an example of a heterotrophic bacterium.

  Escherichia coli
• How do some heterotrophs obtain their cellular constituents?

  From simple sugars like glucose through necessary biosynthetic pathways
• What are the three basic sources of energy for bacteria?

  Light, inorganic compounds, and organic compounds
• How are bacteria classified based on energy requirements?

  • Phototrophs: Use light for energy
  • Chemotrophs: Obtain energy from chemicals
• What do phototrophic bacteria use to generate cellular energy?

  Photosynthesis to generate ATP from light energy
• What do chemotrophic bacteria obtain their energy from?

  Chemicals or chemical compounds
• What are lithotrophs?

  Organisms that use inorganic compounds as electron donors
• How can lithotrophs be further classified?

  Into chemolithotrophs and photolithotrophs
• What are organotrophs?

  Organisms that use organic compounds as electron donors
• How can organotrophs be further classified?

  Into chemoorganotrophs and photoorganotrophs
• What do chemoautotrophs do?

  They oxidize inorganic substances to release energy for synthetic processes
• What is the role of sulphomonas in bacterial nutrition?

  They obtain energy by oxidation of elemental sulphur or H₂S
• What do methanomonas bacteria do?

  They oxidize methane into water and carbon dioxide
• What are fastidious heterotrophs?

  Organisms that require large amounts of vitamins and other growth-promoting substances
• What are the three types of heterotrophic bacteria?

  • Saprophytic
  • Parasitic
  • Symbiotic
• How do saprophytic bacteria obtain their food?

  From dead and decaying organic matter
• What do parasitic bacteria obtain their nutrition from?

  From the tissues of the hosts on which they grow
• What are pathogens?

  Parasitic bacteria that cause diseases in plants and animals
• What is the role of symbiotic bacteria?

  They live in close association with other organisms and are beneficial to them
• What is the function of nitrogen-fixing bacteria?

  To fix atmospheric nitrogen into nitrogenous compounds for plants
• What are the physical requirements for bacterial growth?

  • Temperature
  • pH
  • Oxygen levels
  • Moisture
• What is the role of enzymes in digestion?

  Enzymes digest food and help absorb it.
• What do enzymes break down in the digestive process?

  Enzymes break down complex compounds like carbohydrates and proteins into simpler soluble compounds.
• Name an example of a bacterium that secretes enzymes for digestion.

  Bacillus mycoides
• How do parasitic bacteria obtain their nutrition?

  Parasitic bacteria obtain nutrition from the tissues of their hosts.
• What are parasitic bacteria that cause diseases called?

  Pathogens
• Give an example of a pathogenic bacterium.

  Mycobacterium tuberculosis
• What is the role of symbiotic bacteria?

  Symbiotic bacteria live in close association with other organisms and are beneficial to them.