1. Scientific Method

2. *Bio 1 books from library*
Agenda: 1/7/18
Bellwork: Article with Questions
Bellwork Notebook Setup
Scientific Method Notes
Scientific Method Practice
*Bio 1 books from library*
1st block: 9:30
3rd block: 1:00
4th block: 2:15

3. Scientific Method
The only reason scientists perform experiments is to answer questions.
Observational studies allow scientists to describe a phenomenon.
Determination of what scientists are trying to answer is essential to fulfill comprehension of biology and experimental design.

4. Scientific Method
Types of Questions that can be answer through experimentation:
Questions that involve quantity (numbers)
Questions that include patterns
Questions that includes any concrete behavior (stuff that you can see and record)

5. Scientific Method
Types of Questions that cannot be answer through experimentation:
Questions that involve opinions
Questions that involve feelings or emotions
Questions that involve satisfaction or disappointment

6. What is the effect of light on the movement of Daphnia?
The tiny water flea, Daphnia, is placed in a petri dish under a dissecting microscope. Two minutes after the light has been turned on, the heartbeat is counted for 15 seconds at two-minute intervals. After ten minutes, the Daphnia is removed from the dish and returned to a specimen jar. Which question is this experiment designed to test?
What is the effect of light on the movement of Daphnia?
What is the effect of increasing heat on the heart rate of Daphnia?
How is the circulation of Daphnia affected by different amounts of water?
How is the heart rate of Daphnia affected by different amounts of water? b

7. Can different bacteria live on agar containing proteins?
A teacher prepares agar for six petri dishes on which to grow E. coli bacteria. The table shows the contents of the agar in each petri dish. Based on the information in the table, which of the following questions is the experiment designed to test?
Can different bacteria live on agar containing proteins?
Will agar containing salt prevent bacteria from growing?
What type of agar is best for growing E. coli?
Does E. coli grow at different rates?
Group
Petri Dish
Beef Broth
Chicken Broth
Condensed Milk
Saline X 1 ✔ - 2 Y 3 4 Z 5 6 c

8. Do the birds migrate during the summer?
Some scientists were studying the plants and animals found in the tundra. The scientists noticed that during the winter the number of a specific species of bird increased. Which of the following questions could these scientists not answer through experimentation?
Do the birds migrate during the summer?
Does the death rate increase during the summer?
Is there an increase in hatchlings during the winter?
Are the birds satisfied with food sources during the winter? b

9. Scientific Method
The scientific method is a systemic way to figure out the answer to a problem.
Make an observation or ask a question
Gather information
Create a hypothesis: an educated prediction of what is going to happen
Design and conduct an experiment
Analyze the data
Draw a Conclusion

10. Scientific Method

11. Scientific Method
A hypothesis is an educated prediction of what we think will happen.
Hypotheses are often written as an If…then…. statement.
If..then…statements always make a prediction about what will happen if we change something.
The most important thing to remember is that a hypothesis needs to be something that can be tested.
Saying rap music is better than pop music is not a hypothesis because we cannot test that. Saying more people prefer rap music in this room than country music is a hypothesis because we can test that by taking a poll.

12. Scientific Method
If the data supports our hypothesis, then we can keep it and perform another experiment to see if it still holds true.
If the data does not support our hypothesis, then we will reject the hypothesis.
If many experiments support our hypothesis, then we call it a theory.
Theories have support from many different experiments and many trials of each of those experiments.
If something in science seems to always be true, we call it a law.

13. Scientific Method There are many parts to an experiment.
Constants (controls) – all of the variables that are kept the same so that they do not affect the outcome of the experiment
Experimental group – the group(s) that receive the element that is being tested
Control group – same as experimental group except for the factor being tested (used for comparison)
Replicability – doing an experiment multiple times to make sure that you get the same results over and over.

14. Scientific Method There are many parts to an experiment.
Independent variable - this is the ”factor” that is changed or varies during the experiment to see what happens; it’s the treatment; If our hypothesis was an if…then... Statment, the IV would be the if.
Dependent variable – this is what happens as a “result” of changing the independent variable; it’s the effect or outcome.
This will be what we measure to see what change has taken place. This will be the “then” of our if… then... Statement.

15. Waldo wants to determine which fertilizer, (X, Y, or Z), will cause corn plants to grow the fastest. His hypothesis is that the corn plants fertilized with brand Y will grow the fastest because it contains the most phosphorous. What kind of data should Waldo collect in his experiment? Plant Height. What is the independent variable? Type of fertilizer What would be a good control group for this experiment? Plants that don’t receive any fertilizer What was Waldo’s hypothesis? Waldo believes that brand Y will work best

16. Waldo needs to maintain a constant environment
Waldo needs to maintain a constant environment. Every plant will receive the same amount of light and the same amount of water. Every plant will also be planted in the same soil. Waldo also needs to decide on how many plants per group. He decides 5 plants per group.

17. Scientific Method

18. Graphs
Three main types of graphs:
Bar Graph: Used to compare data between groups
Line graph: Used to compare data for an independent variable that is continuous (can get larger and smaller like time or temperature)
Pie Chart: Used to show parts of a whole. The information is given as percentage.

19. Graphs Parts of a Graph: Title – goes across top.
Axes labels or legend – gives you information on what they represent and how they are measured.
X-axis – the horizontal side (always has the independent variable
Y-axis – the vertical side (always has the dependent variable)

20. Graphs What was the hottest day of the week?
From which two days had the greatest temperature change?

21. Experimental Validity
Ways to increase validity of an experiment:
Add a control group
Control all factors in an experiment that can affect the results
Increase sample size/number of subjects/number of groups being tested
Repeat the experiment to see if you get the same outcome

22. Experimental Validity
Several flaws can decrease the validity of an experiment:
Forgetting to have a control.
A control is needed in order to tell if a change has taken place.
If you don’t have a control, you don’t know if changing the IV has caused a change in the DV (you have nothing to compare the experimental group to!).

23. Experimental Validity
Several flaws can decrease the validity of an experiment:
Having more than one IV.
If we manipulate more than one thing, it is impossible to know which manipulation caused the differences we see in the DV.
This is why you only have one IV and everything else is kept constant.

24. Experimental Validity
Several flaws can decrease the validity of an experiment:
Not replicating the experiment.
If you only do it once, you cannot tell if that is the result you will always get.
Replicability allows you to prove that this will always happen.
Part of replicability is having a large sample size when we do experiments-if your sample is small, it is difficult to conclude that something happens all the time.

25. Bellwork Questions for 1/8/18

26. The size of the pot in which the plants are grown
Students investigate how soil pH affects the height of tomato plants. Each of six tomato plants receives the same amount of light each day and is planted in the same size pot and given the same amount of water. Each plant is planted in soil with a different pH. What is the dependent variable in the investigation?
The size of the pot in which the plants are grown
The pH of the soil in which the plants are grown
The amount of water given to the tomato plants
The height to which the tomato plants grow d

27. Formulate a hypothesis Draw a conclusion Propose a theory
A student is investigating the time it takes for tap water, bottled water, and salt water to reach their boiling point. After the student collects and analyzes the data, what is the next step student should perform according to scientific processes?
Formulate a hypothesis
Draw a conclusion
Propose a theory
Make an observation b

28. Tomato plants grown in soil with no fertilizer
When testing the benefits of a new fertilizer on the growth of tomato plants, the control group should include which of the following?
Tomato plants grown in soil with no fertilizer
Tomato plants grown in soil with the original type of fertilizer
Tomato plants grown in a different type of soil with the new fertilizer
Tomato plants of different varieties grown in soil with the new fertilizer a

29. a

30. c

31. j

32. d

33. f