Chapter 1 The Science of Biology

(What is science?) The Nature of Science

Science is… Based on EVIDENCE (observations). Subject to CHANGE.

Science is… Based upon the assumption that natural laws operate today as they did in the past and will continue to do so in the future.

Science is… Characterized by a common set of values including Logical thinking Precision Open-mindedness Skepticism Reproducibility of results Honest and ethical reporting of results Objectivity/An attempt to avoid bias Imagination (creativity)

Science is… ONE WAY of knowing used by many people (not just scientists). CANNOT ANSWER ALL QUESTIONS.

Facts, Laws & Theories Observations vs. Inferences

FACT the world’s data Ex: Plants need water to survive.

LAW predicts what will happen if certain conditions are present Ex: Newton’s Second Law F = ma (Force = mass x acceleration) * Look for the equations!

THEORY well tested explanation based on observations Ex: natural selection

Observations Using the five senses to gather information. The apple is red.

Types of Observations: Quantitative: involve measuring and the use of numbers. For example: The plant grew 5 cm in the last 7 days. Qualitative: involve descriptions. For example: The plant is growing more on the side that is facing the sunlight.

Inferences A logical interpretation based on ones prior knowledge and experiences. For example: The plant is growing toward the light because it needs light for photosynthesis.

Practice These tracks are representative of fossilized tracks commonly found in parts of New England and the Southwestern U.S.. What are some observations we can make about these tracks? AND are they quantitative or qualitative observations? What are some inferences we can make about the tracks?

More Information What are some new observations we can make about these tracks? Are they quantitative or qualitative? What are some new inferences we can make about the tracks?

And More Information Final observations? Final inferences?

Scientific Method

Note: There is no set order to the scientific method!!!

State the PROBLEM. Usually a QUESTION about what you want to learn. RESEARCH the topic. Form a HYPOTHESIS. HYPOTHESIS = an educated guess or solution based on your research.

Set up the EXPERIMENT. Include the MATERIALS LIST and PROCEDURES. Identify the independent variable, the dependent variable, and the control.

INDEPENDENT VARIABLE = the variable that is changed. ***Note: It is a good idea to have only ONE independent variable at a time! DEPENDENT VARIABLE = the variable that responds to the change and is observed. CONTROL = experiment where nothing is changed.

Collect data. CHARTS and GRAPHS are good. Form a CONCLUSION. Accept or reject your hypothesis. REPEAT your work. COMMUNICATE your findings.

Talking to Plants M Record the following for this experiment: 1.) Question 2.) Hypothesis (If… then…) 3.) Independent Variable 4.) Dependent Variable 5.) Initial Results

Characteristics of Life

biology: study of life organism: any living thing

All living things: 1.) Made up of cells. 2.) Reproduce. (sexually or asexually) 3.) Based on a genetic code. (DNA) 4.) Grow and develop.

All living things: 5.) Obtain and use materials and energy. (metabolism) 6.) Respond to changes in it's environment. ex: Plant growing toward light. stimulus: signal an organism responds to response: the reaction 7.) Maintain a stable internal environment. (homeostasis) Ex: body temperature 8.) Adapt and evolve. (change over time)