1. Biology and The Scientific Method

2. What is Biology? Biology is the study of life Biologist study:
How living things work
How living things interact with each
other and the environment
How living things change over time
3 main branches, bio means life

3. The Scientific Method
The scientific method is -an organized way of learning about how the natural world works. -a careful, organized series of steps taken to answer questions -a natural/instinctive human process
Series of step with one before the other, natural not supernatural (Thunder example Zeus vs. electricity), Must be able to test
Answer

4. Steps of the Scientific Method
There are 6 main steps:
Make an observation
Ask a question and do research
Form a hypothesis(possible explanation)
Design an Experiment
Collect and analyze data
Draw Conclusions
Steps proceed in this order. Nearly impossible to go out of order.

5. Observations The process of science begins with an observation.
ObservationQuestionsExperimentation
Example: I see people using fertilizer on their plants

6. Arrange seats

10. Switch places

16. What do you see in this picture?

18. What do you see in this picture?

20. Observation vs Inference
Skin is purple- observation
Grape is edible- inference
Skin is smooth- observation
Skin is easily broken- inference
There are seeds inside the grape- inference
Have sharp teeth- observation
Have huge bodies- inference
Fighting over females/territory- inference
Spend a lot of time in water- Inference
Hippos have small tails- inference

21. Go to PDF

22. What’s your observation?
Possible inferences ?
Possible inferences ?
The building is on fire
The sprinklers malfunctioned
The sprinklers are being tested
Someone pulled the fire alarm as a prank
It rained
The sprinkler was on
There is dew on the grass from the morning
A dog peed on the grass

23. Asking a Question
At the beginning of every experiment you should state the question you hope to solve by doing your experiment
Example: Does fertilizer cause plants to grow
faster?

24. Forming a Hypothesis
A hypothesis is an educated explanation of how an aspect of the natural world works
When forming a hypothesis remember:
-It should be based on research (no guessing)
-It is one possible answer to your question
-It must be testable
-It is not always correct and that’s okay
-It is posed as a statement of what you think will happen in your experiment based on what you have already observed
Example: I think that plants grown with fertilizer will grow faster than plants grown without fertilizer because…

25. Experimental Scenario #2
Forming a Hypothesis
Experimental Scenario #2
A student investigated the effect of radiation on the germination of bean seeds. He thought that exposure to radiation would limit the seeds ability to germinate (grow) much like ultra-violet light causing skin cancer. Three hundred seeds were soaked in distilled water for one hour. They were then divided into three groups. One group was placed in a microwave oven on high for three seconds. Another group was microwaved on high for six seconds. The last group was not microwaved. The seeds were then planted in three separate flats and given the same amount of water. The seeds were then planted in three separate flats and given the same amount of water. The flats were placed in a location with a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the number of seeds that germinated each group was recorded.

26. Forming a Hypothesis-Experimental Scenario #3
A student investigated the effect of aged-grass compost (fertilizer made from decaying plant material) on the growth of bean plants. She thought that the compost would provide extra nutrients and make plants grow faster. Thirty bean seeds were divided into three groups and planted in different flats (boxes). All seeds germinated after 12 days and were allowed to grow for five days. The flats were ach given the same amount of water and the same amount of light. Flat A was then fertilized with 3-month old compost; Flat B was given 6-month old compost; and Flat C was given no compost. At the end of 14 days the height of each plant was measured in centimeters.

27. Designing an Experiment
Steps to designing an experiment:
-Materials- List and gather materials
-Procedure- plan and record step by step
instructions for how the experiment will
be performed
-Perform the experiment- experiments should be conducted without bias

28. Designing a controlled experiment
In a controlled experiment two identical or near identical groups are formed but only one is tested
Include the more groups the better idea
The control group is not tested so you have a normal standard you can compare results of the experimental group to.
The Experimental group is directly tested 28

29. Designing a controlled experiment
Variables:
The Manipulated/Independent Variable is what you are testing. It is the one thing you do to the experimental group that you do not do to the control group
Responding/dependent variable is what you observe or measure due to the manipulated variable
Include the more groups the better idea 29

30. Designing a controlled experiment
Variables:
What is the manipulated variable in this experiment?
The fertilizer
What would be the responding?
The height of the plants
Include the more groups the better idea 30

31. Manipulated Variable? Responding Variable? Controlled Variables?
Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle.
Manipulated Variable?
Different ages
Responding Variable?
TIME to put the puzzle together
Controlled Variables?
Same puzzle
All of the participants were tested with the same puzzle.
It would not have been a fair test if some had an easy 30 piece puzzle and some had a harder 500 piece puzzle.

32. These were changed by the scientist Responding Variable?
An investigation was done with an electromagnetic system made from a battery and wire wrapped around a nail. Different sizes of nails were used. The number of paper clips the electromagnet could pick up was measured.
Manipulated Variable?
Sizes of nails
These were changed by the scientist
Responding Variable?
Number of paper clips picked up
Controlled Variable?
Battery, wire, type of nail
None of these items were changed

33. On the following 2 examples ID ALL of the following
Controlled group
Manipulated/independent variables
Responding/dependent variables

34. Experimental Scenario #2
Forming a Hypothesis
Experimental Scenario #2
A student investigated the effect of radiation on the germination of bean seeds. He thought that exposure to radiation would limit the seeds ability to germinate (grow) much like ultra-violet light causing skin cancer. Three hundred seeds were soaked in distilled water for one hour. They were then divided into three groups. One group was placed in a microwave oven on high for three seconds. Another group was microwaved on high for six seconds. The last group was not microwaved. The seeds were then planted in three separate flats and given the same amount of water. The flats were placed in a location with a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the number of seeds that germinated each group was recorded.

35. Forming a Hypothesis-Experimental Scenario #3
A student investigated the effect of aged-grass compost (fertilizer made from decaying plant material) on the growth of bean plants. She thought that the compost would provide extra nutrients and make plants grow faster. Thirty bean seeds were divided into three groups and planted in different flats (boxes). All seeds germinated after 12 days and were allowed to grow for five days. The flats were ach given the same amount of water and the same amount of light. Flat A was then fertilized with 3-month old compost; Flat B was given 6-month old compost; and Flat C was given no compost. At the end of 14 days the height of each plant was measured in centimeters.

36. B D C A Different Ages Time to put the puzzles together
Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle.
Different Ages
Time to put the puzzles together
Using the same puzzle
None of the above B D C A

37. 1 - Patty Power
Mr. Krabbs wants to make Bikini Bottoms a nicer place to live. He has created a new sauce that he thinks will reduce the production of body gas associated with eating crabby patties from the Krusty Krab. He recruits 100 customers with a history of gas problems. He has 50 of them (Group A) eat crabby patties with the new sauce. The other 50 (Group B) eat crabby patties with sauce that looks just like new sauce but is really just mixture of mayonnaise and food coloring. Both groups were told that they were getting the sauce that would reduce gas production. Two hours after eating the crabby patties, 30 customers in group A reported having fewer gas problems and 8 customers in group B reported having fewer gas problems.
1.)Which people are in the control group?
2.) What is the independent variable?
3.)What is the dependent variable?
4.)What should Mr. Krabs’ conclusion be?
5.)Write what you think would be a valid hypothesis for this experiment.
6.)Why do you think 8 people in group B reported feeling better.

38. Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweed on the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp. After a week of treatment, the slime is gone and Gary’s shell smells better.
What was the initial observation?
What is the independent variable?
What is the dependent variable?
What should Sponge Bob’s conclusion be?

39. Collecting and Analyzing Data
Data is collected, recorded, and organized throughout an experiment by:
-Using the senses to make detailed descriptions and recording in journals
-Using tools to take measurements (size, volume, weight, temperature, etc.) and recording in tables
Data as numbers (weight, size, time) and data as descriptive observations

40. Data is usually organized into graphs and charts and then analyzed:
-to determine whether the results support or fail to support the hypothesis
-to determine if results are reliable and possible sources of error
-to draw conclusions about the experiment

41. Drawing Conclusions
- After analyzing data you state whether or not your hypothesis is supported.
An experiment can only disprove, not prove a hypothesis.
If a hypothesis is incorrect you form and test a new hypothesis
Conclusion is a summary of the experiment and what happened, nothing is 100%, you want to continue investigating and testing

42. After the experiment
Sources of error Equipment error Human error Experiments must be repeatable with similar results to be accepted
If you got some weird results you want to look at possible sources of error, cold fusion example

43. Hypothesis vs. Theory Theory--Common Meaning:
-contemplation or speculation.
-guess or conjecture.
Theory--Scientific Meaning:
- set of related hypotheses confirmed to be true many times, and can explain a great amount of data
Ex. Cell theory, gravitational theory
Like many words in the English Language

44. Hypothesis vs. Theory continued
Hypothesis: A proposed scientific explanation based on observations that can be tested.
Theory: An explanation that is supported by reasoning, many observations, many experiments and is highly tested and supported.
Don’t copy down but use to state similarities and differences
Similarities Differences

45. # of students receiving each RANGE of scores

46. Ms. Petersen asked her students how long is required to travel from home to school. The information is shown below:
Minutes to School
0–15 16–30 31–45 46–60 61–75 76–90 Frequency