1. Biology Chapter 1 The Study of Life

2. 1.2 Methods of Biology All sciences use what is called the scientific method to investigate natural phenomenon All sciences use what is called the scientific method to investigate natural phenomenon In biology, these phenomenon involve living things In biology, these phenomenon involve living things The scientific method involves the same basic steps, regardless of the branch of science being studied The scientific method involves the same basic steps, regardless of the branch of science being studied

3. 1.2 Scientific Method The scientific method is an organized way to answer a question or solve a problem The scientific method is an organized way to answer a question or solve a problem Depending on how specific your resource, the scientific method generally has 5 or more steps. Depending on how specific your resource, the scientific method generally has 5 or more steps.

4. 1.2 Scientific Method Step 1: Make Observations Step 1: Make Observations Can also include asking a question Can also include asking a question This often happens subconsciously, when you wonder about how or why something is the way it is This often happens subconsciously, when you wonder about how or why something is the way it is Step 2:Form a Hypothesis Step 2:Form a Hypothesis This is a prediction of what you think the results will be This is a prediction of what you think the results will be It could be based on other observations It could be based on other observations Always use “If …. then... Always use “If …. then...

5. 1.2 Scientific Method Step 3: Design & Conduct and Experiment Step 3: Design & Conduct and Experiment This includes gathering materials, designing the experiment, doing the experiment, and recording data This includes gathering materials, designing the experiment, doing the experiment, and recording data Step 4:Analyze results Step 4:Analyze results This includes any calculations you must do as well as organizing and graphing any data This includes any calculations you must do as well as organizing and graphing any data

6. 1.2 Scientific Method Step 5: Drawing a conclusion Step 5: Drawing a conclusion This is when you look at your results and decide what they mean This is when you look at your results and decide what they mean You also decide whether or not your hypothesis was correct You also decide whether or not your hypothesis was correct You can also create more research questions and repeat the entire process at this point, especially if your hypothesis is rejected (it usually is!) You can also create more research questions and repeat the entire process at this point, especially if your hypothesis is rejected (it usually is!)

7. 1.2 Results of the scientific method After many experiments have been done in an area with the same results obtained, theories are often proposed to explain some observation After many experiments have been done in an area with the same results obtained, theories are often proposed to explain some observation Theories are not facts, they are just supported by a lot of data Theories are not facts, they are just supported by a lot of data Once something is generally known to be true, it becomes a law Once something is generally known to be true, it becomes a law These can still be disproven and sometimes are with technological advances! These can still be disproven and sometimes are with technological advances!

8. 1.2 Experimentation In an experiment, you should have an experimental group and a control group In an experiment, you should have an experimental group and a control group The experimental group is the one that recieves the treatment The experimental group is the one that recieves the treatment The control group is the one that has everything the same as the experimental group, but does not receive the treatment The control group is the one that has everything the same as the experimental group, but does not receive the treatment For example: if you were testing the effectiveness of fertilizer: For example: if you were testing the effectiveness of fertilizer: The control group would not receive fertilizer The control group would not receive fertilizer The experimental group or groups would receive fertilizer The experimental group or groups would receive fertilizer

9. 1.2 Types of variables There are 3 types of variables in experiments: There are 3 types of variables in experiments: Independent Independent This is the variable that is being changed or manipulated in the experiment This is the variable that is being changed or manipulated in the experiment Dependent Dependent This is the variable that changes as a result of the independent variable (it is what you are measuring) This is the variable that changes as a result of the independent variable (it is what you are measuring) Controlled (Constant) Controlled (Constant) This is something that is kept the same among all groups in the experiment This is something that is kept the same among all groups in the experiment There are generally multiple controlled variables There are generally multiple controlled variables

10. 1.3 Making Data Tables Data tables involve 2 values, the independent variable and the dependent variable Data tables involve 2 values, the independent variable and the dependent variable Independent variable- Independent variable- Goes in the left hand column of a data table Goes in the left hand column of a data table Dependent variable- Dependent variable- Goes in the right hand column of a data table Goes in the right hand column of a data table For example: if you For example: if you measured the growth of measured the growth of a plant over 5 days, the a plant over 5 days, the # of days would be the # of days would be the independent variable and independent variable and the plant height would be the plant height would be the dependent variable the dependent variable Day Height (cm) 10.05 20.27 30.86 41.11 51.57

11. 1.3 Graphing Data There are 2 primary types of graphs: line graphs and bar graphs There are 2 primary types of graphs: line graphs and bar graphs Line graphs are used for quantitative data (numbers) Line graphs are used for quantitative data (numbers) For example: plant height vs. water volume For example: plant height vs. water volume Bar graphs are used for qualitative data (descriptive) Bar graphs are used for qualitative data (descriptive) For example: favorite colors For example: favorite colors

12. 1.3Aspects of Graphs All graphs must contain some common things, regardless of the type of graph All graphs must contain some common things, regardless of the type of graph Independent variable labeled on the x-axis (horizontal) Independent variable labeled on the x-axis (horizontal) This should include the name of the variable with units, as well as labels on the increments This should include the name of the variable with units, as well as labels on the increments Dependent variable labeled on the y-axis (vertical) Dependent variable labeled on the y-axis (vertical) This should include the name of the variable with units, as well as labels on the increments This should include the name of the variable with units, as well as labels on the increments Title: should indicate both variables and the relationship being examined Title: should indicate both variables and the relationship being examined For example: “Dependent” compared to “Independent” For example: “Dependent” compared to “Independent” Graph should use as much available space as possible, and be evenly spaced Graph should use as much available space as possible, and be evenly spaced

13. 1.3Aspects of Graphs II Other considerations depend on the type of graph Other considerations depend on the type of graph If you are plotting a multiple line graph, a key must be included to identify the lines If you are plotting a multiple line graph, a key must be included to identify the lines Line graphs must have the plotted points connected Line graphs must have the plotted points connected Line graph increments must be marked with the lines of the graph paper Line graph increments must be marked with the lines of the graph paper Bar graph increments must be marked on the space Bar graph increments must be marked on the space

14. 1.3 Common graphing mistakes The following common errors have been identified in graphing on MAP tests: The following common errors have been identified in graphing on MAP tests: Catchy title instead of descriptive one Catchy title instead of descriptive one No units on axis labels No units on axis labels Reversing x-and y axes Reversing x-and y axes Using the wrong type of graph (bar instead of line or vice versa) Using the wrong type of graph (bar instead of line or vice versa) Axis labels not consistently scaled, not evenly spaced and not taking up the whole graph Axis labels not consistently scaled, not evenly spaced and not taking up the whole graph

15. 1.3 Types of Data There are 2 general types of data, qualitative and quantitative There are 2 general types of data, qualitative and quantitative Qualitative data is descriptive data based on general observations Qualitative data is descriptive data based on general observations For example: the apple is red For example: the apple is red Quantitative data is numeric data based on measurements Quantitative data is numeric data based on measurements For example: the apple weighs 56.2 grams For example: the apple weighs 56.2 grams

16. 1.3 Metric System In all sciences, the metric system is used for measuring quantitative data In all sciences, the metric system is used for measuring quantitative data It uses base units (gram, meter, liter, seconds, degrees Celsius) and uses prefixes to show multiples or divisions of those base units It uses base units (gram, meter, liter, seconds, degrees Celsius) and uses prefixes to show multiples or divisions of those base units Common prefixes are: (more on p. 1097) Common prefixes are: (more on p. 1097) Kilo: = 1000 base units Kilo: = 1000 base units Deci= 0.1 base units Deci= 0.1 base units Centi= 0.01 base units Centi= 0.01 base units Milli= 0.001 base units Milli= 0.001 base units

17. 1.3 Converting Metric Units The easiest way to convert metric units is the stairstep: The easiest way to convert metric units is the stairstep: You move the decimal the same direction and number of spaces as you moved on the stairs You move the decimal the same direction and number of spaces as you moved on the stairs Kilo Hecto Deka Base Unit Deci Centi Milli

18. 1.3 Measuring Matter Mass is the amount of matter an object contains and is measured with a balance in grams Mass is the amount of matter an object contains and is measured with a balance in grams Volume is the amount of space an object takes up and is measured with a ruler or graduated cylinder in cm cubed or mL Volume is the amount of space an object takes up and is measured with a ruler or graduated cylinder in cm cubed or mL