In 1668, Francesco Redi performed a series of experiments on spontaneous generation. He placed pieces of meat into eight identical sealed jars. Four jars were left open to the air, and four were sealed. What hypothesis was being tested? The hypothesis being tested was whether spontaneous generation can occur only if meat is exposed to air.
The Correct Answer and Explanation is:
Correct Answer:
The hypothesis being tested was whether spontaneous generation occurs only when meat is exposed to air.
Explanation:
In 1668, Francesco Redi conducted one of the first controlled experiments to challenge the idea of spontaneous generation, which was a common belief at the time. Spontaneous generation was the theory that living organisms could arise from non-living matter. For example, people believed that maggots appeared on rotting meat because the meat itself generated life.
To test this idea, Redi designed a simple but effective experiment using meat and jars. He placed equal amounts of meat into eight identical jars. He left four jars open to the air, and sealed the other four completely. After some time, he observed that maggots appeared only in the open jars where flies could enter and lay eggs, but no maggots appeared in the sealed jars.
The hypothesis Redi was testing was not simply whether air alone causes life to appear, but whether exposure to air was necessary for spontaneous generation to occur. The idea was that if spontaneous generation were true, then maggots should have appeared in the sealed jars too, because the meat was still there. However, since no maggots appeared in the sealed jars, it suggested that maggots came from flies—not from the meat itself.
To refine this further, Redi later did a variation of the experiment using gauze-covered jars that allowed air in but prevented flies from landing on the meat. Again, maggots only appeared on the gauze, not on the meat, strengthening his conclusion.
This experiment helped disprove spontaneous generation and laid the foundation for modern biology and the understanding that life comes from life, not from non-living material.
