How were Redi’s and Pasteur’s experiments on spontaneous generation similar?

• A. Both used controlled experiments to demonstrate that life does not arise spontaneously from nonliving matter.
• B. Both experiments involved boiling broth to kill microorganisms.
• C. Both scientists used swan-neck flasks to prevent contamination.
• D. Both experiments proved that maggots could arise from decaying meat without any external influence.

Answer: (A)

Verified step by step guidance

1. Identify the main goal of both Redi's and Pasteur's experiments: to test the hypothesis of spontaneous generation, which is the idea that life can arise from nonliving matter without any external influence.
2. Examine Redi's experiment: he used controlled setups with meat exposed to air but protected from flies, and meat exposed directly to flies, to show that maggots only appeared when flies could lay eggs, thus using a control to rule out spontaneous generation.
3. Examine Pasteur's experiment: he boiled broth to kill any existing microorganisms and used swan-neck flasks to allow air in but prevent microbial contamination, demonstrating that no microbial growth occurred unless the broth was exposed to contaminants.
4. Compare the experimental designs: both scientists used controls to prevent contamination and carefully designed their experiments to isolate the variable of spontaneous generation, showing that life did not arise without external introduction of organisms.
5. Conclude that the similarity lies in their use of controlled experiments to disprove spontaneous generation, rather than the specific methods like boiling broth or using swan-neck flasks, which were unique to Pasteur.