Lutzkanin 2015 Notify your teacher A Hypothesis B

Lutzkanin 2015

§ Notify your teacher

A. Hypothesis B. Scientific Law C. Experiment D. Variable

A. The medicine is still in the testing stage. B. People should go to the hospital to buy the medicine. C. That the person in the advertisement takes that medicine. D. Medical experts recommend the medicine

A. Scientific Law B. Hypothesis C. Theory D. Variable

A. Independent Variable B. Dependent Variable C. Operational Variable D. Control

A. Variable; control B. Independent variable; dependent variable C. Dependent variable; independent variable D. Variable; constant

A. Observing B. Inferring C. Predicting D. Classifying

A. Bias B. Variable C. Inquiry D. Predictions

§ In 1928, Sir Alexander Fleming was studying bacteria grown in culture dishes. He noticed a mold called penicillin was also growing in some of the dishes. A clear zone existed around the penicillin mold. All the bacteria that had grown in this clear zone had died. In the culture dishes without mold, no clear areas were present. § Fleming decided that the mold must be producing a chemical that killed the bacteria. He decided to isolate this substance and then test it to see if it would kill bacteria. Fleming prepared two beakers of nutrient broth, with had everything that the mold needs to grow and reproduce. He put mold into one of the beakers of nutrient broth. He allowed the mold to grow, and then removed the mold from the nutrient broth, and then he added the broth to a dish of bacteria. Fleming added the nutrient broth that had not had mold growing in it to another dish of bacteria. The bacteria in the dish with nutrient broth that had mold in it were all killed. The bacteria in the dish with nutrient broth that did not have mold in it were not killed. Fleming concluded that the mold produced a bacteria killing substance in the broth. He called the substance penicillin § 1. Identify the problem Fleming wanted to solve. § 2. What was Fleming’s hypothesis? § 3. What was the variable of the experiment? § 4. What was the control? § 5. What was Fleming’s conclusion? § 6. What was the great discovery from Fleming’s experiment?

§ 1. Identify the problem Fleming wanted to solve. § Was the mold killing the bacteria § 2. What was Fleming’s hypothesis? § The penicillin mold killed the bacteria § 3. What was the variable of the experiment? § mold § 4. What was the control? § Dish of bacteria with nutrient broth § 5. What was Fleming’s conclusion? § The mold produced a bacteria-killing substance § 6. What was the great discovery from Fleming’s experiment? § penicillin

Average height (cm) According to the graph, “Time (weeks)” would be the Time (weeks) A. B. C. D. Independent variable Dependent variable Control Constant

§ Independent Variable – amount of brown sugar § Dependent Variable – taste of the cookies § Constants: other ingredients, cooking temperature, cooking time § Control: ½ cup brown sugar 1. 2. 3. 4. 5. 6. Gather ingredients Make 3 batches – each w/ different amounts of brown sugar Have 6 people try 1 of each cookie Record which cookie they thought was best Repeat experiment 2 more times Draw conclusions