introduction to science for biology students measurement the scientific method graphing
TRANSCRIPT
Lab Equipment
• Graduated Cylinder- Measures Volume- Place on table- Eye Level!!- Read at bottom of
curve (meniscus)
• Ruler– Use CENTIMETERS (cm) or MILLIMETERS (mm)– There are 10 millimeters in every centimeter
cm mm
*BREAK*
• Problem: I’m cold.
• Think of some questions that you might ask me in order to solve my problem.
What is the Scientific Method?
• A step-by-step way to solve problems
Steps:
1. State the Problem2. Do Research3. Make a Hypothesis4. Conduct an Experiment5. Collect and Measure Data6. Analyze Data7. Make a Conclusion
1. State the Problem
• The question you are trying to answer• Based on observations you have made
– Observations are made by using your senses (sight, sound, touch, etc.)
– Observations are facts!– Inferences are opinions, or assumptions, based on
your observations
1. State the Problem
• Usually the problem is written as a question• Ex:
What affect does caffeine have on your heart rate?
3. Make a Hypothesis
• States the expected answer to the problem– What do you think the experiment will show?
• Must be able to be tested!
• Written in an “If…. Then…” format
If you drink a soda with caffeine, then your heart rate will be higher than if you drink a soda without caffeine.
4. Perform an Experiment
• The procedure used to test your hypothesis
• Hypothesis: If you drink a soda with caffeine, then your heart rate will be higher than if you drink a soda without caffeine.
• Your experiment needs to have:– Sodas with caffeine– Sodas without caffeine– People to drink the soda and measure their heart rate
• In an experiment, you test one variable at a time– A variable is something that changes
Independent Variables (IV) – what YOU change on purpose; is known before the experiment
Dependent Variable (DV) – what you measure in the experiment; is NOT known before the experiment
Controls: a variable that you keep the same throughout the experiment
Variables
• In our experiment, we have:– Sodas with caffeine– Sodas without caffeine– People to drink the soda and measure their heart
rate
• What is the Independent Variable?• What is the Dependent Variable?• What are some controls?
Answers..
• IV = caffeine• DV = heart rate• Controls = same amount of soda, same age
people, possibly same gender, same amount of time, or same person
5. Collect and Measure Data
• There are two types of data:– Quantitative = numbers– Qualitative = descriptions
• What type of data would… be…– The plant is green– The plant is 2cm tall
6. Analyze Data
• Once you have measured your data, you can arrange it in graphs or tables
- This will allow you to see any trends in your
data
Caffeine
No Caffeine
Heart rate
Graphs• There are 3 types of graphs:– Line = shows information over TIME– Bar = shows ONE TIME information– Circle/Pie = shows percentages or parts of a whole
Hamburgers Hot Dogs Corn Dogs012345
Students
Students
8
10
2
1 3
Grades
ABCDF
7. Form a Conclusion• You summarize what you discovered in your
experiment• You state whether your hypothesis was correct
or incorrect• Written in complete sentences!• Ex:
A person’s heart rate is higher after drinking a soda containing caffeine than after drinking a soda that does not contain caffeine.