1. Chapter 1.2

2. 1. Asking a Question 2. Forming a Hypothesis (MUST be testable) 3. Setting up a Controlled Experiment 4. Recording and Analyzing Results (data) 5. Forming Conclusions

3.  Spontaneous Generation states that life can arise from nonliving matter -- like rotting meat making maggots -- mice being found in grain -- beatles and bugs being found on poop

4.  Redi did not think that life could just spontaneously appear from other nonliving things.  He decided to challenge this idea by applying the scientific method and testing a hypothesis

5.  What could be done to test whether or not meat can “spontaneously generate” maggots (baby flies)  Lets think of an experiment to perform to prove this right or prove this wrong

7.  Many people still believed in spontaneous generation  They said that air (or oxygen) is required for this to occur – spontaneously!!!!  ANOTHER SCIENTIST THEN STEPPED IN  Louis Pasteur designed an experiment to settle this absurd idea

8.  Pasteur designed a flask with a long curved tube coming off the top  The bacteria was unable to reach the broth, but it was still open to the environment… meaning oxygen could still reach the broth  No bacteria grew!!!!!

10.  Pasteur made many discoveries related to microorganisms  His work showed that infectious diseases were a result of microorganisms entering the bodies of the victims

11.  As the evidence builds up, a particular hypothesis may become so well supported that scientists accept them as a THEORY  This is what happened to the hypothesis that new organisms come from existing organisms  This is now referred to as “Biogenesis” – generating from life

12.  In science, the word THEORY applies to a well tested explanation that unifies a broad range of observations  A theory allows scientists to make accurate predictions about new situations

13. 1. How did Pasteur’s experiment put an end to the idea of “spontaneous generation”??

14. 2. How does a scientific theory compare with a scientific hypothesis?

15. 3. How do scientists today usually communicate their results and conclusions?