What is Science?
What is Science? FACTS based on observations: information from senses organizing evidence to learn about the natural world based on observations: information from senses
Observation and Inference When using the “scientific method” you need to use your Observation Skills. An observation involves using one or more of the senses to gather information. You also may have to use Inference An inference is a logical interpretation based on prior knowledge and experience.
2 types of Observations A Quantitative Observation involves numbers, such as counting or measuring. (data collection) A Qualitative Observation involves characteristics that cannot be easily measured or counted, such as color or texture.
What is Biology? The study of living things (organisms) The study of interactions between living things bio= life ology= study of
Scientific Method
Why? Battery? Gas?
How could you test battery?
What if it still didn’t start?
Is it out of gas??
Scientific Method Ask a question Formulate a hypothesis Design and conduct and experiment Collect and analyze data Make a tentative conclusion Test conclusion, if necessary, refine question & go through each step again
Scientific Method Ask a question Formulate a hypothesis Why won’t the car start? Formulate a hypothesis Dead battery? Design and conduct and experiment Try the lights… Try jump starting… Collect and analyze data Do the lights go on? Does it start with jumper cables? Make a tentative conclusion If not dead battery… does the car have gas? Test conclusion, if necessary, refine question & go through each step again
Conclusion C. Data E. Hypothesis Pop Quiz: Identify the following examples of components of the scientific method. Conclusion C. Data E. Hypothesis Control group D. Experimental group F. Problem A chart with the number of roaches killed and the treatments they received. I wonder what will kill a roach? Roaches are killed more quickly when sprayed with Raid than if sprayed with water. One group of roaches is sprayed with Raid If roaches are sprayed with Raid, then they will die quickly. One group of roaches is sprayed with water
Conclusion C. Data E. Hypothesis Pop Quiz: Identify the following examples of components of the scientific method. Conclusion C. Data E. Hypothesis Control group D. Experimental group F. Problem A chart with the number of roaches killed and the treatments they received. C I wonder what will kill a roach? F Roaches are killed more quickly when sprayed with Raid than if sprayed with water. A One group of roaches is sprayed with Raid. D If roaches are sprayed with Raid, then they will die quickly. E One group of roaches is sprayed with water. B
Designing an Experiment Controlled Experiment One variable IV vs DV
Independent Variable Dependent Variable
Experimental Design
Hypothesis The plant exposed to fertilizer will grow taller
What am I testing? What is my hypothesis? What am I measuring? How will I know if my hypothesis is supported?
Independent Variable IV Manipulated Variable The thing you are testing
Dependent Variable DV Responding Variable The thing you are measuring as a result of exposure to the IV
Parts of a Graph Title y axis dependent variable (unit) x axis independent variable (unit)
Parts of a Graph MIX DRY Title y axis dependent variable (unit) x axis independent variable (unit)
Independent Variable: the thing you are testing (CAUSE) Dependent Variable: the thing you are measuring (EFFECT)
Independent Variable: the thing you are testing (CAUSE) Dependent Variable: the thing you are measuring (EFFECT)
Collecting Data
Discrete Data Discrete Data can only take certain values. Example: the number of students in a class (you can't have half a student). Example: the results of rolling 2 dice: can only have the values 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12
Continuous Data Continuous Data can take any value (within a range) A person's height: could be any value (within the range of human heights), not just certain fixed heights Time in a race: you could even measure it to fractions of a second A dog's weight The length of a leaf
Pop Quiz (Quantitative? Qualitative?) My biology teacher is funny The new restaurant in town is fancy The school cafeteria is more crowded during “A” lunch than “B” lunch The boys in 1st block biology are taller than the boys in 2nd block biology Our class has a lot of school spirit The birds are so colorful this time of year