Question

Spallanzani’s experiment proved
A) Air is necessary for spontaneous generation
B) Air from outside, while entering the flask carried small bacteria
C) Air is unnecessary for spontaneous generation
D) The contents of flask could not be boiled properly

Answer 1

Hint: Spontaneous generation is a hypothesis in which it is proposed that the living organism can be produced from the non-living matter like air. This theory is proposed during the study of evolution and based on this theory many scientists have given new theories of evolution.

Complete Answer:
To solve this question, we have to know details about the lazzaro Spallanzani experiment.

- In his experiment he takes two separate bottles consisting of broth and boils the broth of both the bottles. Then kept one bottle open and another one sealed and incubated it overnight.
- The next day, the bottle which is kept unsealed shows a tiny living organism that he can observe clearly under a microscope.
- The sealed bottle does not show any growth. This makes the spontaneous generation a viable theory.
- This theory gets accepted when scientists start believing that the theory of spontaneous generation that is derived by Spallanzani needs air for spontaneous generation.
- So, Spallanzani’s experiment proved that air from outside the bottle is the reason behind the bacterial growth.

Hence, the correct answer is ‘B’. Air from outside, while entering the flask carries small bacteria.

Additional information:
The articulation of the theory of spontaneous generation is done by Aristotle, he had given the concept that life can originate from non-living matter. Aristotle proposed that if the material contains vital heart or pneuma the life can originate from the non-living material.

Note: For several centuries scientists used to believe in the concept of spontaneous generation but later many experiments related to this were carried out that proves that the living organism that can grow from non-living matter can be dissolved and this theory proved false.