AP BIOLOGY

Detailed explanation-1: -Louis Pasteur’s 1859 experiment showed that a boiled nutrient broth did not give rise spontaneously to new life, but that if direct access to air was permitted, the broth decomposed, implying that small organisms (in modern terms, microbial spores) had fallen in and started to grow in the broth.

Detailed explanation-2: -Louis Pasteur is credited with conclusively disproving the theory of spontaneous generation with his famous swan-neck flask experiment.

Detailed explanation-3: -According to the theory of spontaneous generation, living organisms can arise from non-living matter. Louis Pasteur disproved this theory and was awarded for the same.

Detailed explanation-4: -After prolonged incubation the swan necked flask remained free of life, whereas the control flask was teeming with microbial life. Thus, Pasteur succeeded in disproving the spontaneous generation theory because the swan neck of the flask allowed only air, and not the microbes.

Detailed explanation-5: -Louis Pasteur is credited with conclusively disproving the theory of spontaneous generation with his famous swan-neck flask experiment. He subsequently proposed that “life only comes from life.”