Microbiology: The Science

• Microorganisms - are organisms that are too small to be seen with the unaided eye.
• Microbiology - are organisms that are too small to be seen with the unaided eye.
• Parasitology - is the study of parasites, their hosts, and the relationship between them
• Categories of Microorganisms

  Viruses, Bacteria, Archaeans, Algae, Protozoa, Fungi
• Germs - microorganisms that cause disease
• Pathogens - disease-causing microorganism
• Nonpathogens - do not cause disease
• Indigenous Microflora or Mircrobiota - are beneficial; inhibit growth of pathogens by occupying space
• Opportunistic Pathogens (Opportunists) - do not usually cause problems, but have potential to cause infection (e.g. Escherichia coli)
• Decomposers - decompose organic waste
• Saprophytes - live on dead or decaying matter
• Microbial Ecology - study of relationships bet. microbes and the environment
• Biotechnology – use of microorganisms in industry
• Genetic engineering - a new technique for biotechnology that involves the transfer of genes from one organism to another
• 2 Categories of Disease

  Infectious Disease & Microbial Intoxication
• Category of Disease

  Infectious disease – pathogen colonizes body and subsequently causes disease
• Category of Disease

  Microbial intoxication – when a person ingests toxin (poisonous substance) produced by a microorganism
• First Microorganism on Earth

  Archaeans and Cyanobacteria – candidates for the first microorganisms on earth
• Pioneers in the Science of Microbiology

  Anton van Leeuwenhoek, Louis Pasteur, Robert Koch
• Theory of Abiogenesis - The idea that life can arise spontaneously from non living material; Also called Theory of Spontaneous Generation
• Germ Theory of Disease - specific disease is caused by specific microorganism
• Pasteurization – kill pathogens in many types of liquids through heating
• Koch's postulates - are four criteria designed to establish a causal relationship between a causative microbe and a disease.
• Careers in Microbiology

  Bacteriology, Phycology, Protozoology, Mycology, Virology