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Welcome to

Biol 178

Principles of Biology

• Course goals• Course information• Text• Grading• Syllabus• Lab• Chapter

Organization

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What is Biology?Study of life

Search for order in the natural world

Discovery of new relationships

Learn working rules that allow life to exist

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•Concept Outline

•Text

•Interim Summaries

•Summary Tables

•Concept Review

•Self Test Questions

•Challenge Questions

Chapter Organization & Aids to Promote Learning

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Lecture Outline

• A view of Life Characteristics of living organisms• Organization of life:

Levels of organization How to do Science

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Lecture Outline 1Reading Assignment: Chapter 1

• A view of Life:• Characteristics of living organisms• A. Cellular organization• B. Metabolism• C. Homeostasis• D. Reproduction• E. Heredity• F. Adaptability• G. Growth• H. Response• I. Other

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Levels of Organization

• Cellular Organization• cells• organelles• molecules• atoms

• The cell is the • basic unit of life.

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Levels of Organization

• Organismal Level•

organism• organ systems• organs• tissues

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Levels of Organization

• Population Level•

ecosystem•

community• species• population

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LifeLevels of Organization

1.Among organisms

2.Within Organisms

3.Within Cells

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Consequences of Hierarchical organization

• Emergent properties• New properties arise at each

higher level

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Unifying Themes of Biology

• 1. Cells• 2. Molecular basis of inheritance -

DNA• 3. Structure & function are

interrelated• 4. Evolution produces diversity• 5. Evolutionary conservation• 6. Life has emergent properties

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How is science done?

• Science aims to understand the natural world through observation and reasoning.

• Science begins with observations, therefore, much of science is purely descriptive.

• Science uses both deductive and inductive reasoning.

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The Nature of Science

• Deductive reasoning uses general principles to make specific predictions.

• Inductive reasoning uses specific observations to develop general conclusions.

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The Nature of Science

• Scientists use a systematic approach to gain understanding of the natural world.

• -Observation• -Hypothesis formation• -Prediction• -Experimentation• -Conclusion

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The Nature of Science

• A hypothesis is a possible explanation for an observation.

• Hypothesis leads to a prediction.

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The Nature of Science

• The experiment

• -tests the hypothesis by testing prediction

• -must be carefully designed to test only one variable at a time

• -consists of a test experiment and a control experiment

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The Nature of Science

Prediction True Conditionally Accept Hypothesis

False Reject Hypothesis

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Limitations of Science

• Hypothesis can NOT be proven true

• Truth Table• Hypothesis Prediction• True True• False

False or True

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Limitations of Science

Science does not prove hypotheses are true.

Science proves that some hypotheses are not true.

Hypotheses not proven false are conditionally accepted.

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Hypotheses, Theories & LawsHypothesis

• a tentative explanation.

Scientific Theory• Accepted explanation.• Supported by experimental evidence.• Solid ground of science.• A well-supported hypothesis.

Scientific Law• Scientific knowledge accepted as true.• An extremely well-supported hypothesis.

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END