Disproving Spontaneous Generation using the experiments of Pasteur and Spallanzani
Summary:
This video summarizes the experiments performed by Lazzaro Spallanzani and Louis Pasteur and their attempts to disprove the theory of spontaneous generation using Legos as visual aid. Spontaneous generation is when life forms from any type of non-life. Lazzaro Spallanzani performed an experiment in which he boiled broth to kill al the microorganisms and then sealed the flask. Then, he waited and re-examined the flask to find no microorganisms present. This experiment however only proved that spontaneous generation cannot occur without oxygen. Louis Pasteur performed a similar experiment. However, instead of sealing the flask, he designed one with a curved opening. This way, oxygen could get in but microorganisms couldn't. This disapproved spontaneous generation because it proved that even in the presence of oxygen, life couldn't be created from non-life.
Relevance:
This video is relevant to unit three because we started of the unit discussing the cell theory and how people in early times thought spontaneous generation occurred to create life. The theory of spontaneous generation is where life can come from any non-life. For example, people used to believe that maggots could appear from meat. In class, we discussed Lazzaro Spallanzani's and Louis Pasteur's experiments to disprove spontaneous generation and this video shows what they did using Legos to show it.
Video Information:
YouTube url: http://www.youtube.com/watch?v=laP2Pqkzeso
Author: Matt99Bio
Date of Publication: March 18, 2012
When did all these expiriments happen? And where?
ReplyDeleteLazzaro Spallanzani's experiment happened in the late 1700's in Italy and Pasteur's experiment happened in the mid 1800s in France. I couldn't find an exact year because different sources say different years.
DeleteActually I found that Louis Pasteur's experiment was performed in 1859.
Deletehttp://www.accessexcellence.org/RC/AB/BC/Spontaneous_Generation
Did anyone else do similar experiments, or were these the only two people in that time frame who bothered?
ReplyDeleteGood question James. In class we learned about Francesco Redi's experiment in 1668 which kind of started all of these experiments. Because this was such a controversial topic, people didn't want to believe it and many people did experiments. In 1745, and Englishman named John Needham performed a similar experiment. After him came Spallanzani and Pasteur and after him, no one bothered because he disproved it.
DeleteSource: http://www.accessexcellence.org/RC/AB/BC/Spontaneous_Generation.php