2. What is the Scientific Method? An___________ approach to perform an ____________ Organized experiment

4. 1. Define________ 1. A problem can't be solved if it isn't ____________ 2. Write the problem in the form of a ____________ 3. Ex: How does smoking affect a person’s breathing rate during exercise? Problem understood question

5. 2. Form a __________ 1. A __________ based on __________ and ___________ 2. Written in the form of a _________. 3. Ex: I think that a smoker will have a higher breathing rate during exercise than a non-smoker. Hypothesis Prediction research Observations statement

6. 3. Do the _________ 1. Experiments test the _____________ 2. The experiment will prove whether or not your hypothesis was ________________________ 3. Every experiment needs at least ____________________ Experiment hypothesis Correct or incorrect Three groups (variables)

7. a. Experimental Group – consists of _________variables i. Dependent Variable i. Dependent Variable - What you are in ______________the experiment –Ex: breathing rate, heart rate, blood pressure, height of plant, etc. ii. Independent Variable ii. Independent Variable - conditions _________________ by experimenter –smokers vs. nonsmokers two measuring varied or changed

9. Control Group: b. Control Group –all ________ are kept _____________ to insure that they do not affect the ___________ of experiment –EX: age, weight, gender, length of exercise, # years smokingvariables constant outcome

11. 4. Results/Observations 1. __________ and ________ ____ 2. Includes _______,________,________ etc. Record analyze data charts graphs statistics

12. 5. Conclusions: 1.In it's simplest form, the conclusion will be "yes" the hypothesis was __________ or "no" the hypothesis was _____________. 2.All experiments should be _________________ 3. All experiments should be ___________ over and over again to assure accuracy correct not correct Peer-reviewed repeated

15. Why does Bread turn Moldy?

16. Bread Mold As you know, we keep food in refrigerators so it will last longer. But still, sometimes you open a bag of bread or a jar of spaghetti sauce and what do you find? Mold!! Ever wonder exactly what mold is? And how did it get there? And why sometimes it’s green and other times black or white? Did you know this stuff is alive and growing?

17. Bread Mold In this experiment, you’ll find out all about those colorful, fuzzy fungi by growing your own crop. Note: This is a long-term activity. It will take several days for the mold to grow. The first day should take about 30 minutes to one hour. For safety reasons, don’t eat or drink while doing this experiment. And don’t taste or eat any of the materials used in the activity.

18. 2. Wash your hands. Place a slice of white bread in the bag labeled "Dry White Bread" and seal the bag. –Using one eye dropper, sprinkle 20 drops of tap water on another slice of white bread. (Don’t overdo it; the bread should be moist, not wet. If your bread is dripping, you’ve definitely done way too much. Throw away that slice and try again.)

19. Materials: 3 eye droppers small cup filled with 4 teaspoons or 20 mL of sugar water small cup filled with 4 teaspoons or 20 mL lemon juice small cup filled with 4 teaspoons or 20 mL tap water 4 slices of plain white bread 4 slices of assorted bread, such as wheat, rye, sourdough, etc. 8 resealable plastic sandwich bags marker masking tape

20. Procedure: 1.Using masking tape and marker, make labels for four sandwich bags. Label the first bag "Dry White Bread." Label the second "Water on White Bread," the third "Lemon Juice on White Bread," and the fourth "Sugar Water on White Bread."

21. Place the moist bread in the bag marked "Water on White Bread" and seal the bag. Using a different eye dropper, sprinkle 20 drops of lemon juice on another slice of white bread and put it in the bag marked "Lemon Juice on White Bread" and seal the bag. Using your third eye dropper, sprinkle 20 drops of sugar water on the last slice of white bread and place it in the bag labeled "Sugar Water on White Bread" and seal. Try to keep your fingers off moist spots when handling each slice of bread.

22. 3. Repeat steps 1 and 2, but this time use a different kind of bread in the remaining four bags. Your labels should note what kind of bread you’re using. Wash your hands when you’re done.

23. 4. Make sure all of your bags are tightly sealed. Place all eight bags in a dark, warm place (about 86 degrees Fahrenheit, 30 degrees Celsius). Check the bags each day for two weeks and record the results in a notebook. You may wish to draw or take pictures of the bread slices. Don’t open the bags!

24. 5. Make a graph recording the total growth of mold on each of the four white bread slices at the end of two weeks Make a similar graph for the other four bread slices. Compare the results. At the end of the two weeks, throw out all the bags unopened

25. Sample Graph:

26. Questions: What is your hypothesis? What were the variables used in your experiment? What was the control? Could factors other than water and sunlight have influenced your results? Explain.

27. Additional Questions: 1.From this activity can you tell what helps mold to grow best? 2.Does it matter what kind of bread you use? 3.What causes the different colors you see? 4.What would happen if you left the bags in a well-lit place instead of a dark place? 5.What would happen if you changed the temperature?

29. 1. From this activity can you tell what helps mold to grow best? Unless you used bread that had been sitting out for many days, you probably didn’t get much or any mold growth on the dry bread. Clearly, water is important for the growth of mold. The mold grew best on bread sprinkled with sugar water because the sugar serves as food for the fungi. The more food that’s available, the more fungi cells can grow. The mold also grew pretty well on the bread with plain tap water because the fungi could use the sugar and starch in the bread as food. The mold didn’t grow as well on the bread sprinkled with lemon juice because lemon juice is acidic. Acids hinder the growth of many common fungi and bacteria.

30. 2. Does it matter what kind of bread you use? Molds grow better on some kinds of breads than others depending on the ingredients used and how the bread was made. Some breads are dry and some are moist. The amount of the sugar in different breads varies; some have sugar, honey or molasses added. Some breads are even acidic, such as sourdough. Some may have fruit or nuts or other ingredients added.

31. Many commercial breads are made with preservatives that hinder the growth of molds and bacteria to prevent or delay spoilage. Bread baked fresh in a bakery that doesn’t use preservatives will more likely become moldy faster. All of these factors can influence how much mold will grow on a particular kind of bread.

32. 3. What causes the different colors you see? Many of the colors you see on the moldy bread are due to the spores the fungi have produced. Molds reproduce by making spores at the end of stalks that rises above the surface of the bread, giving molds a fuzzy appearance. Spores are like seeds—they spread molds to new places so that they can continue to grow. Spores are usually colorful.

33. Fungi: Some fungi, such as Rhizopus nigricans (rye-zoh-puss neye-grih- cans) and Aspergillus niger (As-per- jill-us neye-jer), make black spores. Neurospora crassa (new-rah-spore- ah crah-sah) produces spores that appear pink. And the Penicillium (pen-ih-sill-ee- um) molds, the molds that make penicillin, are blue-green.

34. Bacteria: Some of the colors on your bread may be the result of growing colonies of bacteria, which also sometimes grow on old food. For example, a bacterium called Serratia marcescens (ser-ay-shuh mar-seh-sens) forms reddish colonies. You can tell bacteria colonies apart from molds because bacteria colonies appear smooth while molds look fuzzy.

35. 4. What would happen if you left the bags in a well-lit place instead of a dark place? Molds grow best in the dark, so not as much mold would be present on bread slices kept in a well-lit place.

36. 5. What would happen if you changed the temperature? Most fungi grow best around room temperature. But they can grow at a range of temperatures from cold (like in a refrigerator) to quite warm (body temperature). At temperatures colder or warmer than their favorite temperature, they usually do not grow as rapidly. If the temperature is too cold or too hot, they will not grow at all, and may even be killed.