Chapter 1 Flashcards
What is a microbe?
a living organism that requires a microscope to be seen
What are the three contradictions to the general definition of a microbe?
- Supersize microbial cells
- Microbioal Communities
- Viruses
What is a prokaryote and what are examples of them?
A prokaryote is a simple cell that lacks a nucleus. Examples are bacteria and archaea.
What is a eukaryote and what are examples of them?
A eukaryote is a complex cell that has a nucleus. Examples are algae, fungi, and protists.
What is a genome?
the total genetic information contained in an organism’s chromosomal DNA
Who developed the first method of DNA sequencing fast enough to sequence large genomes?
Fred Sanger
What was the first bacterium that the first genome sequence completed on?
Haemophilus influenzae
What is a metagenome?
The collection of sequences taken directly from the environment
How have microbes shaped human culture?
- Yeasts and Bacteria for foods and beverages.
2. “Rock-eating” bacteria for mining metals
What microbial disease devastated human populations in the 14th Century?
Bubonic plague caused by Yersinia pestis
What microbial disease devastated human populations in the 19th Century?
Tuberculosis caused by Mycobacterium tuberculosis
What microbial disease devastates the human populations today?
AIDS/HIV
Who was Florence Nightingale?
- British Nurse who recognized the significance of diseases in warfare
- founded the science of medical statistics
- Showed the deaths of soldiers due to various causes, she devised the “polar area chart”
Who built the first compound microscope, published Micrographia, and coined the term “cell”?
Robert Hooke
Who built single-lens magnifiers, complete with sample holder and focus adjustment and was the first to observe single-celled microbes?
Antonie van Leeuwenhoek
What is spontaneous generation?
The theory that living creatures could arise without parents
Who showed that maggots in decaying meat were the offspring of flies?
Francesco Redi
Who showed that a sealed flask of meat broth sterilized by boiling failed to grow microbes?
Lazzaro Spallanzani
Who discovered the microbial basis of fermentation, “swan-neck” flasks, and showed that, after boiling, the contents remain free of microbial growth, despite access to air?
Louis Pasteur
What is the Germ theory of disease?
Many diseases are caused by microbes
Who founded the scientific method of microbiology, and applied his methods to numerous lethal diseases around the world?
Robert Koch
What is the chain of infection and who demonstrated it?
- transmission of a disease
- Robert Koch
What medium did Angelina and Walther Hesse use for pure culture?
Agar
What did Julius Petri use to get a pure culture?
Double-dish containter
What are Koch’s four postulates?
- Microbe is always present in diseased host.(absent in healthy)
- Microbe is grown in pure culture.(no other microbes present)
- Pure microbe is introduced into healthy host. (individual becomes sick)
- Same microbe is re-isolated from now-sick individual.
Who introduced the practice of smallpox inoculation to europe in 1717?
Lady Mary Montagu
Who deliberately infected patients with matter from cowpox lesions? What was this called that is a common name today?
Edward Jenner
“vaccination”
Who developed the first vaccines based on attenuated(weakened) strains?
Louis Pasteur
What is an immunization?
The stimulation of an immune response by deliberate inoculation with an attenuated pathogen
Who ordered doctors to wash their hands with chlorine an antiseptic agent in 1847?
Ignaz Semmelweis
Who developed carbolic acid to treat wounds and clean surgical instruments in 1865?
Joseph Lister
When was aseptic surgery developed?
20th century
Who studied tobacco mosaic disease and found that the agent of transmission could pass through a porcelain filter that blocked all known microbes?
Dmitri Ivanovsky
Who concluded that the agent of tobacco must be something other than a bacterium?
Martinus Beijerinck
How many microbial species can be cultured in the laboratory?
less than .1%
Who discovered lithotrophs, developed enrichment cultures, and built the Winogradsky column?
Sergei Winogradsky
What are endosymbionts?
They are microbes living symbiotically inside a larger organism.
What were the two challenges taxonomist faced when attempting to classify microbes?
- Resolution of the light microscope was too low.
2. Microbial species are hard to define.
Who called prokaryotes living in hot springs and those that produced methane Archaea?
Carl Woese
Who replaced the classification scheme of five kingdoms with three equally distinct groups: Bacteria, Archaea, and Eukarya?
Carl Woese
Who developed the electron microscope and what does it reveal?
- Developed by Ernst Ruska
2. Revealed internal structure of cells
Who developed the ultracentrifuge and what does it enable?
- Theodor Svedberg
2. Enabled separation of subcellular parts
Who discovered the transformation in bacteria?
Frederick Griffith
Who showed that the transforming substance is DNA?
Oswald Avery
Who used X-Ray crystallography to determine that DNA is a double helix?
Rosalind Franklin
What is the hypothetical world without DNA called?
RNA World
