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History of Microbiology; Spontaneous Generation


History of Microbiology; Spontaneous Generation Nestor T. Hilvano, M.D., M.P.H. Learning Objectives You should be able to: Describe the contributions of Leeuwenhoek. – PowerPoint PPT presentation

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Title: History of Microbiology; Spontaneous Generation

History of MicrobiologySpontaneous Generation
  • Nestor T. Hilvano, M.D., M.P.H.

Learning Objectives
  • You should be able to
  • Describe the contributions of Leeuwenhoek.
  • List six groups of microorganisms.
  • Differentiate between prokaryotic and eukaryotic
  • List and answer four questions that propelled
    research into what is called the Golden Age of
  • Compare and contrast the investigations of Redi,
    Needham , Spallanzani, and Pasteur to disprove
    spontaneous generation.
  • Discuss the significance of Pasteur's
    fermentation experiments to our world today.
  • Identify the scientist whose experiments led to
    the field of biochemistry and the study of
  • Name two scientists whose work with vaccines
    began the field of immunology.
  • List four major questions that drive
    microbiological investigations today (modern age
    of microbiology).
  • Identify the field of microbiology that studies
    the role of microorganisms in the environment.

Introduction to Microbiology
  • Branch of biology that deals with the study of
    microscopic forms of life.
  • Microbes short for microorganisms, single-cell
    life forms that can be seen through a microscope
    some are beneficial and others are harmful
  • Anton van Leeuwenhoek
  • made the first _____ microscope to examine the
    qualities of cloth.
  • - reported protozoa (1674) bacteria (1676)
  • Compound b. Simple
  • Electron d. dissecting

Microbes Classification
  • Carolus Linnaeus Taxonomic System, grouping
    similar organisms together
  • 2 Types of Cell- Eukaryotes or Prokaryotes
  • ___ unicellular, lack a nucleus (DNA in
    cytoplasm ?nucleoid) bacteria
  • and archaea
  • ___ cells with nucleus (DNA in nucleus)
    fungi, algae, protozoa,
  • 6 groups
  • Bacteria 2. Archaea 3. Fungi
  • Protozoa 5. Algae 6. Little animals
  • Viruses smallest microbes, neither eukaryotes
    nor prokaryotes obligate intracellular parasites
  • Ex Ebola virus is disastrous in humans, but
    the virus can be safely
  • carried by its natural host (bats,
    monkey, chimp).

  • Differ from plants b/c they obtain food from
    other organisms differ from animals b/c they
    have cell wall include
  • a.) Molds multicellular, grow as filaments
    (hyphae) reproduce by spores cottony growth on
    cheese, bread, jams
  • b.) Yeasts unicellular, oval reproduce by
  • Exercises
  • __ molds that produce penicillin
  • __ yeasts which cause bread to rise and produce
    alcohol from sugar
  • __ yeast infection in female
  • a. Candida albicans b. Penicillium chrysogenum
  • c. Saccharomyces cerevisiae d. Escherichia coli

  • Single-celled eukaryotes, unicellular most
    capable of locomotion
  • Live freely in water, some cause disease
  • Locomotive structures
  • ___ cell extension during its travel in
  • ___ hair-like projection that beat
    rhythmically in Paramecium
  • ___ whip-like cell in Trypanosoma (african
    sleeping sickness)
  • a. cilia b. flagella c. pseudopodia

  • Plant-like eukaryotes photosynthesis
  • Seaweeds and kelps, large algae
  • Glasslike cell walls (diatoms) of algae
  • Serve as food for marine animals and make
    chemicals used in microbiological growth media
    (solid agar culture)

Bacteria and Archaea
  • Single-celled prokaryotes
  • Reproduce asexually
  • Bacteria - peptidoglycan cell walls most are
  • Archaea cell wall composed of other polymers
  • Exercises
  • __ What type of microbes is found in extreme
    environment (such as acidic hot spring, high
    saline lake, or oxygen depleted swamps)?
  • a. Archaea b. Bacteria

  • Acellular, obligatory intracellular parasites
  • Smallest microbes, neither eukaryotes nor
  • composed of small amounts of genetic material
    (DNA or RNA) surrounded by a protein coat.
  • Was discovered until the invention of EM in 1932
  • Ex Ebola virus is disastrous in humans, but the
    virus can be safely carried by its natural host
    (bats, monkey, chimp).

4 Events during the Golden Age of Microbiology
  1. Is spontaneous generation of microbial life
  2. What causes fermentation?
  3. What causes disease?
  4. How can we prevent infection and disease?
  • 1. Proved that living things come from other
    living things
  • 2. 3. Microorganisms can cause fermentation and
  • 4. Certain procedures and chemicals can prevent
    and cure infectious diseases

Is Spontaneous Generation of Microbial Life
  • John Needham
  • - boiled beef gravy and infusions of plant
    materials in vials, sealed with cork revealed
    life force
  • Francesco Redi - in sealed flask, decaying meat
    was kept from flies, maggots never developed
  • Lazzaro Spallanzani
  • - boiled infusion and sealed vials by melting
    their necks closed reported results that
    contradicted Needhams findings
  • Louis Pasteur
  • - father of microbiology experiments with
    swan-necked flask, upright flask, no microbial
  • Exercises Which of the above scientists
    disproved spontaneous generation?

Pasteurs Contributions Father of Microbiology
  • Began the field of industrial microbiology
    (biotechnology) microbes are intentionally used
    to manufacture products.
  • Discovered that bacteria ferment grape juice to
    produce acids whereas yeast cells ferment grape
    juice to produce alcohol
  • Pasteurization use of heat to kill pathogens
    and reduce the number of spoilage of microbes in
    food and beverages (asepsis).

Buchners Experiments
  • Demonstrated the presence of enzymes that promote
    chemical reactions
  • Began the field of biochemistry and the study of

Infection and Disease Prevention
  • Semmelweis (handwashing), Lister (antisepsis
    phenol), Nightingale (hygiene), and Snow (public
    hygiene) investigations laid the foundation of
    infection control and epidemiology
  • Edward Jenner, showed that vaccination with pus
    collected from cowpox lesions prevented smallpox
    (field of immunology).
  • Later Pasteur, develop vaccines against fowl
    cholera, anthrax, and rabies.
  • Ehrlichs search for magic bullets, discovered
    chemicals effective against syphilis and sleeping
    sickness (field of chemotherapy).

Modern Age of Microbiology
  • Biochemistry study of metabolism practical
    applications like design of herbicides and
    pesticides, diagnosis of illnesses, treatment of
    metabolic diseases, and design of drugs to treat
  • Microbial genetics study of inheritance in
  • Molecular biology combines aspects of
    biochemistry, cell biology, and genetics to
    explain cell function at the molecular level
  • Genetic engineering (recombinant DNA technology)
    manipulation of genes for practical
  • Gene therapy use of recombinant DNA to
    insert a
  • missing gene or repair a defective gene
    in human.
  • Environmental microbiology

Environmental Microbiology
  • Studies the role microbes play in their natural
  • - biodegradation
  • - role in the causation of disease
  • - control the spread such as sewage
  • treatment, water purification, and
  • sanitation measures

  1. Define terms microbiology, molds, yeast,
    protozoa, algae, viruses, biotechnology,
    pathogen, microbes, spontaneous generation,
    bacteria, archaea, genetic engineering, and
  2. Why was Pasteur considered as the Father of
  3. Name 3 scientist who disproved spontaneous
  4. Name the contributions of Leewenhoek.
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