This document provides an introduction to the principles of biology. It begins with questions students may have about the class. It then defines what science and biology are and discusses the importance of scientific literacy. The document outlines the key characteristics of living things and the three domains that make up the tree of life. It introduces the scientific method and discusses how scientists study the natural world through experiments that test hypotheses. The summary concludes by defining science as understanding nature through objective evidence, measurements, and reproducible experiments.

2. Principles of Biology
Starts with questions.
Am I in the correct class?
Do I need to write this down?
Do I have to buy the book?
Will we have lab today?

3. What is science?

4. What is biology?

5. WHY?

8. Scientific Literacy
The knowledge and understanding of scientific
concepts and processes required for personal
decision making, participation in civic and cultural
affairs, and economic productivity.
http://blogs.discovermagazine.com/intersection/2009/03/17/what-is-scientific-literacy/#.Wa8FvrKGOCh

9. 9
Image PowerPoint slides to accompany
An Introduction
to Biology
Chapter 1

10. Learning Objectives:
The Scientific Study of Life
By the end of this section, successful students
should be able to:
1. Describe the characteristics shared by living
organisms.
2. Compare and contrast the three branches of life.
3. Apply the scientific method to analyze data.
4. Identify standardized, dependent, and
independent variables in an experiment.
5. Interpret data and draw conclusions from graphs
and tables.
6. Discuss the limitations of the scientific method.

11. What is Life?

12. • Organized
• Requires energy
• Homeostasis
• Reproduction, growth, and development
• Evolution

13. Section 1.1 Figure 1.2
CELL
The Characteristics of Life
Life is organized
ORGANELLE
MOLECULE
ATOM

14. Organization

15. Section 1.1
Life requires energy
Energy
from
sunlight
Heat
Heat
Heat
Heat
Figure 1.4
Producers
Consumers
Decomposers

16. Figure 1.5
Life maintains Homeostasis

17. Life reproduces, grows,
and develops

18. Figure 1.7
Life evolves

19. The Tree of Life Includes Three
Main Branches
Taxonomy

20. The Tree of Life Includes Three
Main Branches
DOMAIN BACTERIA DOMAIN ARCHAEA

21. The Tree of Life Includes Three Main Branches
Amoeba: © Melba Photo Agency/PunchStock RF
DOMAIN EUKARYA
Protista (multiple kingdoms) Kingdom Animalia
LM
200 μm
Kingdom Fungi Kingdom Plantae

22. Hierarchical Organization
–Domain (3)
•Kingdom
–Phylum
»Class
• Order
• Family
• Genus
• Specific epithet (species)

24. Scientists Study
the Natural World

25. Figure 1.10
Scientific
Method

28. Types of Science
Figure 1.11
Scientists test their
hypotheses with
discovery science or
controlled experiments.
Section 1.3 Birdwatcher: U.S. Fish & Wildlife Service/J&K Hollingsworth; Coffee tasters: © Corbis RF

29. Experimental Design
1.
2.
3.
4.
5.

30. Variables
• Independent variable: what is manipulated
(e.g., type of coffee bean)
• Dependent variable: what is measured
(e.g., amount of caffeine)
• Standardized variable: held constant for all
subjects in an experiment (e.g., mass of
beans)
Well-designed experiments include independent,
dependent, and standardized variables.
Coffee tasters: © Corbis RF

31. Figure 1.12

32. Think in graphs!
Independent
Dependent
Standardized Variables:
This Photo by Unknown Author is licensed under CC BY-SA-NC

33. Statistics
• Statistically Significant

35. Bias

36. Hypothesis vs. Theory

37. Scientific Thinking:
• Different from other ways of thinking
• Use of evidence to answer questions and test
ideas.
1. Quantifiable
2. Testable
3. Repeatable

38. Different ways of thinking about
(understanding) the world.

40. Science cannot answer EVERYTHING!

41. What is Science?
• Understanding how nature works, based on
objective evidence that includes reproducible
experimental data and measurements and
observations.
Objective vs. Subjective

42. Characteristics of Science
• It is guided by natural law.
• It has to be explained by these natural laws.
• Science is testable against the natural, observable world.
• Its conclusions are tentative, that is, are not necessarily the
final word. (e.g. Science is self-correcting and admits
mistakes).
• It is falsifiable, meaning that science will seek out errors and
correct them. Unlike other philosophies, it’s a self-correcting
system. This is how progress is often made.
• One cannot prove things true or false in science. Probability
plays a role.
• Correlation does not imply Causation.

43. Criteria for Determining Science
• Science is logical and rational
• Science makes well-defined claims
• Scientific hypotheses are falsifiable
• Scientific experiments are repeatable
• Science requires that claims be
examined by peers
• Science views unexplained gaps in
theories with suspicion
• Science requires caution in examining
evidence
• Science requires objectivity (open-
mind)
• Science does not accept coincidence
as proof
• Science does not accept anecdotal
evidence as proof.
• Science relies on measurable,
repeatable evidence.
• Science insists that extraordinary
claims require extraordinary
evidence.
• Absence of evidence is not evidence
of absence.