Lecture 1 Powerpoint Flashcards
(47 cards)
Define microbiology
The branch of biology dealing with the structure, function, uses, and modes of existence of microscopic organisms.
True or false: Microbiology usually includes immunology, as well as the methods and technology used to study microbes
True
What 4 fields of study fall under the broad term ‘microbiology’?
Virology, mycology, parasitology, bacteriology
What did Jainism (600bc) and Mahavira believe about microbiology?
Mahavira asserted the existence of unseen microbiological creatures living in earth, water, air, and fire
The ancients called microbes “________ _______” and the Greeks called them “________ _______”
Ancients: ‘invisible spirits’
Greeks: anthropomorphic gods
What did the Roman Marcus Terentius Varro say about microbiology?
“there are certain minute creatures which cannot be seen by the eyes, which float in the air and enter the body through the mouth and nose and thereby cause serious diseases”
What was the prevailing theory of illness through the end of the 1800s?
The Miasma theory of bad air/ poisonous vapor
Girolamo Fracstoro (1546) asserted that disease is caused by invisible creatures placed in 3 categories; what were those 3 categories?
1) Those that infect by contact
2) Those that infect by fomites (any surface an “invisible creature” could be on)
3) Those that infect by distance
A lot of people denied the existence of microbes until we could see and study them, which happened during what century?
17th century (1600s)
What was the theory of spontaneous generation?
the theory that living organisms could develop from nonliving matter
What were the 3 pieces of evidence those who supported spontaneous generation used?
The ‘spontaneous generation of’:
1) Maggots on meat
2) Frogs on mud
3) Mice from grain
What was John Needham (1748)’s experiment in support of spontaneous generation, and why was the experiment flawed?
He applied heat to a broth and put a stopper on it; over time the broth became turbid. He asserted that it was sterile broth and that the creatures creating the turbidity spontaneously generated.
However, it was not sterile because the bottle of broth was open briefly after heating, and it may not have been boiled (unsure because Needham took terrible notes).
Who were the people who conducted the first two experiments that challenged spontaneous generation?
1) Francesco Redi (1665)
2) Lazzaro Spallanzani (1765)
What was Francesco Redi (1665)’s experiment?
He put one piece of meat in an unsealed flask, one in a flask sealed by a cork, and one flask covered by gauze. The unsealed flask had flies, maggots, ands eggs on it; the sealed flask had nothing on it; the flask covered with gauze had flies and fly eggs on the gauze because the flies could smell the meat.
What was Lazzaro Spallanzani (1765)’s experiment?
He heated broth and air in an open flask, and the flask became turbid. Then the did the same thing in a sealed flask, and the flask remained clear.
What was the experiment of Schwann and von Dusch (19th century)?
They found that if air was filtered through a cotton filter and attached to an otherwise sealed, previously heated flask, the flask would remain clear as long as the cotton filter was there.
What experiment did Louis Pasteur (late 19th century) conduct that helped disprove the theory of spontaneous genration?
He applied heat to two containers of unsterile broth, sterilizing them, and broke the neck of the first sterile flask, but kept the neck of the second sterile flask intact. He found that the microbes were trapped at the base of the second flask and it remained clear, but that the first flask became turbid.
What were Pasteur’s 4 major contributions to science?
1) Pasteurization: a technique invented by Louis Pasteur to sterilize liquid.
2) Vaccines: Pasteur helped create a couple vaccines.
3) Crystals: studied crystals and organic chemistry.
4) Microbial fermentation; certain microorganisms are able to take sugars and convert them into something different.
In 1836 and 1845 the fungal origin of what two diseases was discovered?
Silkworm disease and potato blight
Describe the effects of potato blight in the 1800s
-By 1800, the potato became the staple of life for Irish peasants
-In 1845, a “queer mist” came over the Irish Sea
Potato stalks turned black; potatoes began to putrify (smell bad)
-40% of the crop was destroyed
-Desperate for food, people ate anything they could scavenge (‘The Great Hunger’)
-Malnutrition leads to susceptibility to disease
-Began the process of migration (only ⅕ made it, so their ships were called ‘coffin ships’)
-Cause of the Great Hunger: having a single-crop economy
-Role of Potato Blight in World War I
Who is known as the “Father of modern infection control”?
Ignaz Simmelweis
Describe the discovery of Ignaz Simmelweis
In 1847 his midwives found that adequate hand hygiene can prevent transmission of puerperal fever
In 1867 _______ ________ created a method for the sterilization of operating instruments and antiseptic practice
Joseph Lister
What was Friedrich Henle’s major contribution towards microbiology?
In 1840, Friedrich Henle’s work began the “germ theory” of disease; wrote a famous essay called “On Miasma and Contagia”
