BMSC210 CH3.1 Flashcards
What is the theory of spontaneous generation?
Life can spontaneously arise from non-living matter
Who were some individuals who tried to prove or disprove spontaneous generation?
van Helmont, Redi, Needham, Spallanzani, and Pasteur
Who proposed the theory of spontaneous generation?
Aristotle
What was Aristotle’s evidence for spontaneous generation?
Appearance of animals in previously devoid environments
What was the design of Pasteur’s flasks?
Long, twisted necks
What was the purpose of Pasteur’s flasks?
To sterilize broth
What did the design of the flasks prevent?
Introduction of airborne microorganisms
Why would a life force have access to the broth in the sterilized flasks?
Microorganisms would not have access
What did he predict about sterilized broth in swan-neck flasks?
Would remain sterile if swan necks intact
What would happen if the swan necks were broken?
Microorganisms would be introduced and contaminate the flasks
What would happen if the flasks were contaminated?
Microbial growth within the broth would occur
What theory did Pasteur’s experiments disprove?
Spontaneous generation
What was the outcome of Pasteur’s experiments?
Proof that life only comes from life
Who definitively refuted the theory of spontaneous generation?
Louis Pasteur
What feature of the flasks used in Pasteur’s experiment prevented the entry of bacterial and fungal spores?
Swan-neck
