BIOL260 Ch. 1
Who was the first to observe bacteria?
Anthony van Leeuwenhoek (1632-1723)
Dutch drapery merchant
How were the first bacteria seen?
In a drop of lake water through a ground glass lens
What did van Leeuwenhoek call them?
Who first observed a microorganism?
What was it?
Robert Hook 1665
Microscopical mushroom...now identified as common bread mould
Who should be given credit for discovering micro-organisms?
Both van Leeuwenhoek and Hooke
What is the theory of spontaneous generation?
Who debunked it?
Organisms can arise spontaneously from non-living material
Francesco Redi at end of 17C
Demonstrated that worms on rotten meat came from the eggs of flies...covered meat with gauze to stop flies...no worms appeared
John Needham and Father Spallanzani
Both boiled solutions...Needham's grew microorganisms....Spallanzani did not
Why? Longer boiling time and sealed necks of glass jars by melting glass...not using porous cork.
Who was the father of modern microbiology?
How did Pasteur disprove spontaneous generation in 1861?
What piece of equipment did he devise?
Demonstrated air is full of microorganisms...filtered air through cotton plug...dropped plug into sterilized infusion...became cloudy...organisms multiplied
Swan necked flask
Who finally proved Pasteur correct?
Different infusions required different boiling times to become sterile.
What was the most heat resistant infusion of Tyndall?
What was his conclusion?
Heat resistant forms of microorganisms could exist
What is the heat resistant form of a bacteria?
Who discovered endospores?
German botanist, Ferdinand Cohn 1876
Who discovered anthrax?
Robert Koch 1877
What causes anthrax?
When was anthrax used in the US by bio terrorists ?
Why were organisms that produce endospores found on the hay?
They are commonly found in soil
Two reasons that it took so long to disprove the theory of spontaneous generation
Scientists did not understand the importance of the source of their infusions...too many variables
It is essential to reproduce all conditions of an experiment as closely as possible
What experiment disproved the notion that a vital force in the air was responsible for spontaneous generation?
Pasteur's experiment with the swan-necked flask
If Pasteur's swan necked flasks had contained endospores, what results would have been observed?
Boiling would not have sterilized the broth and cloudy growth would have been observed
Microbes include living and non-living forms
T or F?
Living members of the microbes
Some multi-cellular parasites
Non living members of the microbe family
Most common feature of most members of the microbe family?
Can only be seen with the aid of a microscope
Microbes are extremely diverse and share few common properties?
T or F?
What is biodiversity?
Variety of species present in a particular environment