Introduction to Biology
Chapter 1
Biology is the study of LIFE!
Big Ideas in AP Biology Big Idea 1: The process of evolution drives the diversity
and unity of life.
Big Idea 2: Biological systems utilize free energy and molecular building blocks to grow, to reproduce and to maintain dynamic homeostasis.
Big Idea 3: Living systems store, retrieve, transmit and respond to information essential to life processes.
Big Idea 4: Biological systems interact, and these systems and their interactions possess complex properties.
Themes in the Study of Life
1. Biological Hierarchy 1. Atom
2. Molecule -> macromolecule
3. Cells
4. Tissue
5. Organ & organ system
6. Organism
7. Population
8. Community
9. Ecosystem (biomes)
10. Biosphere
2. Organisms interact with other organisms & environment
3. Life requires energy transfer
4. Structure dictates Function (Form fits function)
5. The Cell = Basic unit
6. Continuity of life is based on heritable information
7. Feedback mechanisms
8. Evolution accounts for unity and diversity of life
Taxonomy: classification of organisms
Three Domains of Life
1. Bacteria
2. Archaea
3. Eukarya (plants, animals, fungi)
What is Science?
• Science = Latin “to know”
Inquiry is at the heart of science. • Inquiry: search for information and
explanation
Two main processes: 1. Discovery science 2. Hypothesis-based science
Discovery Science
• Describes nature through observation and analysis of data
• Data = recorded observations
– Qualitative and quantitative
• Inductive reasoning: derive generalizations based on specific observations
specific general
Hypothesis-Based Science
• Hypothesis: makes predictions that can be tested by recording more observations or experiments
Deductive reasoning (general specific)
• If … , then …
• Predict outcomes of experiments if hypothesis is correct
The Myth of the Scientific Method
• Published research articles follow the steps of the “textbook” scientific method
• Most scientific inquiries don’t follow this structured form
• Scientists can be working with the wrong hypothesis and have to redirect research
• Discovery science - contributes to understanding of nature without using the “scientific method”
Experiments
• Hypothesis (If …, then ...)
• Use control and experimental groups
Independent Variable – what is manipulated/changed in the experiment
Dependent Variable – what is measured
If [independent variable], then [dependent variable].
Hypothesis / Theory / Law
Hypothesis • Explanation to specific
question
• Prediction
• Educated guess
• Tested by experiment or continued observation
• Can be disproven, but not can’t proven to be true
Theory • Summarizes group of
hypothesis supported by repeated testing
• Broader in scope
• New hypotheses can be generated from it
• Supported by massive body of evidence
Scientific Law • Statement of fact
• Explains things, but doesn’t describe them
• Generally accepted to be true and universal
• Basis for scientific method
