Classes of Microorganisms

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• Classes of Microorganisms

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Classes of Microorganisms

• Non-pathogenic
• normal
• do not produce disease
• beneficial
• Pathogenic
• cause infection and disease
• May be non-pathogenic in one body system,
  pathogenic in another (E. coli)

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Classes of Microorganisms

• Aerobic
• requires oxygen to live
• Anaerobic
• does not require oxygen to live

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Classes of Microorganisms

• 6 classes of microorganisms
• Bacteria
• Protozoa
• Fungi
• Rickettsiae
• Viruses
• Helminths

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Classes of Microorganisms

• Bacteria
• Often considered the causes of disease
• Certain bacteria
• produce antibiotics
• live in the body without problems
• live on the roots of certain plants, converting
  nitrogen into a usable form
• help break down dead organic matter
• Classified by shape and arrangement
• Treated with antibiotics

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Classes of Microorganisms

• Bacteria
• Cocci-
• round in shape
• diplococci
• streptococci
• staphylococci

Streptococci
Staphylococcal clusters
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Classes of Microorganisms

• Bacteria
• Bacilli
• rod shape
• single
• pairs
• chains
• may have flagella
• may form spores
• difficult to treat

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Classes of Microorganisms

• Bacteria
• Spirilla
• spiral or corkscrew shape
• vibrio
  - spirochete

Treponema pallidum
Cholera
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Classes of Microorganisms

• Bacteria
• Some bacteria develop resistance to antibiotics
• Very difficult to cure
• Methicillin-resistant Staphylococcus (MRSA)
• Multidrug-resistant Staphylococcus (MDSA)

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Classes of Microorganisms

• Protozoa
• One celled, animal-like organism
• Contain a nucleus and other defined organelles

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Classes of Microorganisms

• Fungi
• organisms that usually enjoy a symbiotic, but
  sometimes parasitic relationship with their host
• provide numerous drugs and foods
• provide bubbles in bread, champagne, and beer
• cause a number of plant and animal diseases
• fungal diseases are very difficult to treat

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Classes of Microorganisms

• Fungi

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Classes of Microorganisms

• Rickettsiae
• rod-shaped, parasitic bacteria
• live in the tissues of ticks, fleas, and lice
• transmitted to humans through bites
• invade the new host from within

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Classes of Microorganisms

• Viruses
• small, infectious agent
• requires a host for survival
• over 5,000 types
• can combine in multiple ways to produce a wide
  range of diseases
• produce immune response in humans
• treated with antiviral drugs

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Classes of Microorganisms

• Helminths
• Parasitic worm-like organisms
• Live inside the host
• Feed off their host
• Disrupt nutrient absorption
• Lead to weakness
• Excrete toxins making host susceptible to other
  diseases
• Approximately 30 billion people globally are
  infected

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Classes of Microorganisms

• Bacteria
• Protozoa
• Fungi
• Rickettsiae
• Viruses
• Helminths