General Microbiology and the History of Medical Microbiology

A comprehensive set of vocabulary flashcards covering the basics of microbiology, classification, key historical figures, experiments disproving spontaneous generation, and milestones in molecular biology and immunology.

Microorganisms

Unicellular (single-celled) microscopic organisms.

Prokaryotes

A classification of microorganisms that includes Bacteria and Archaea.

Protists

One-celled eukaryotes.

Estimated Global Microbe Population

$5 \times 10^{30}$ microbes, compared to a human population of $7 \times 10^9$.

True pathogens

Microbes capable of causing disease in healthy persons with normal immune defenses, such as the Influenza virus or malarial protozoan.

Opportunistic pathogens

Microbes that cause disease when the host's defenses are compromised or when they grow in a part of the body that is not natural to them, such as $Pseudomonas$ spp. or $Candida\text{ }albicans$.

Normal flora

Microbes usually found associated with animal body tissue that prevent invading pathogens.

Probiotics

Live microorganisms that may provide health benefits to the host and can be added to the diet through foods like Lactic acid bacteria.

Prebiotics

Specific substances used as food for normal flora.

Biotechnology

The exploitation of microbes for the production of antibiotics, enzymes, and various chemicals, as well as genetic engineering to generate products like insulin.

Robert Hooke ($1635$-$1703$)

First to observe cells (cork cells) using a self-manufactured microscope, providing the foundation for Cell Theory.

Antonie van Leeuwenhoek ($1632$-$1723$)

Dutch linen merchant and the first to observe living microbes using a single-lens microscope magnified up to $300 \times$.

Edward Jenner ($1749$-$1823$)

The Father of Immunology who pioneered clinical trials for vaccination by using cowpox rash pus to provide immunity against smallpox.

John Snow ($1813$-$1858$)

The Father of Epidemiology who traced the source of a $1854$ cholera epidemic in East London to a contaminated well on Broad Street.

Spontaneous Generation

The belief that "Life spontaneously arises" from non-living matter, such as meat turning into maggots.

Biogenesis

The concept of "Life Begets Life," asserting that living things only come from other living things.

Lazzaro Spallanzani

Discovered in $1799$ that heated and capped liquid resisted spoilage indefinitely, though critics argued air was needed to activate life.

Louis Pasteur ($1822$-$1895$)

The "Father of Microbiology" who disproved spontaneous generation using a swan-necked flask, developed pasteurization, and demonstrated the Germ Theory of Disease.

Robert Koch ($1843$-$1910$)

Established Koch’s postulates to verify germ theory, developed pure culture methods, and identified the causes of anthrax, TB, and cholera.

Germ Theory of Disease

The theory that many diseases are caused by the growth of microbes in the body rather than factors like sins or poverty.

Enrichment culture

A growth medium tailored to suit a particular microbial metabolic function.

Microbial ubiquity

The concept that "everything is everywhere, the environment selects."

Martinus Beijerinck ($1851$-$1931$)

Isolated nitrogen fixers and sulfur reducers and coined the term "virus" after determining Tobacco Mosaic Disease was caused by an agent smaller than bacteria.

Hans Christian Gram ($1853$-$1938$)

Developed the Gram Stain method for distinguishing between two major classes of bacteria.

Sir Alexander Fleming ($1881$-$1955$)

Discovered the enzyme lysozyme in $1923$ and the antibiotic penicillin from the fungus $Penicillium\text{ }notatum$ in $1928$, winning a Nobel Prize in $1945$.

Avery, MacCleod, and McCarty ($1944$)

Discovered that the "transforming principle" responsible for changing non-infectious R pneumococcal cells into infectious S cells was DNA.

Fred Sanger ($1977$)

Developed methods to determine the exact sequence of DNA.

Kary Mullis ($1985$)

Invented PCR (polymerase chain reaction) using a heat-stable DNA polymerase from the bacterium $Thermus\text{ }aquaticus$.

FMT

Fecal microbiota transplantation, a procedure related to the study of gut microbiota and its role in disease.

Hologenome theory of evolution

The framework discussed regarding how symbiotic bacteria like $Lactobacillus$ can influence mating preferences and speciation in $Drosophila\text{ }melanogaster$.