10. OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat. HYPOTHESIS: Flies produce maggots. PROCEDURE Controlled Variables: jars, type of meat, location, temperature, time Manipulated Variables: gauze covering that keeps flies away from meat Uncovered jars Covered jars Several days pass Maggots appear No maggots appear Responding Variable: whether maggots appear CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur. Redi’s experiment Spontaneous Generation – Life arises from non- living things

11. 06/08/09 Gravy is boiled . Flask is open. Gravy is teeming with microorganisms. Gravy is boiled . Flask is sealed. Gravy is free of microorganisms . Section 1-2 Figure 1-10 Spallanzani’s Experiment Spallanzani’s Experiment Theory not supported “vital force in air was killed”

12. Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Pasteur intro Figure 1-11 Pasteur’s Experiment Pasteur’s Experiment Pasteur changed 1 variable in the experiment – he used a curved neck flask

13. Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Section 1-2 Figure 1-11 Pasteur’s Experiment The curved neck of the flask allowed air to mix in the jar but not bacteria

14. Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Section 1-2 Figure 1-11 Pasteur’s Experiment

15. Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Section 1-2 Figure 1-11 Pasteur’s Experiment Once the neck was removed bacteria entered and spoiled the broth