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Chapter 1: An Introduction to Life on Earth At a Glance

Case Study: : Life on Earth—and Elsewhere?

1.1 What Are the Characteristics of Living Things?

• Living Things Are Both Complex and Organized
• Living Things Respond to Stimuli
• Living Things Maintain Relatively Constant Internal Conditions Through Homeostasis
• Living Things Acquire and Use Materials and Energy
• Living Things Grow
• Living Things Reproduce Themselves
  DNA Is the Molecule of Heredity
• Living Things As a Whole Have the Capacity to Evolve

1.2 How Do Scientists Categorize the Diversity of Life?

• The Domains Bacteria and Archaea Consist of Prokaryotic Cells; the Domain Eukarya Is Composed of Eukaryotic Cells
• Bacteria, Archaea, and Protists Are Mostly Unicellular; Members of the Kingdoms Fungi, Plantae, and Animalia Are Primarily Multicellular
• Members of the Different Kingdoms Have Different Ways of Acquiring Energy

1.3 What Is the Science of Biology?

• Scientific Principles Underlie All Scientific Inquiry
  Natural Causality Is the Principle That All Events Can Be Traced to Natural Causes
  The Natural Laws That Govern Events Apply Everywhere and for All Time
  Scientific Inquiry Is Based on the Assumption That People Perceive Natural Events in Similar Ways
• The Scientific Method Is the Basis for Scientific Inquiry

Scientific Inquiry: Does Spoiled Meat Produce Maggots?

• Science Is a Human Endeavor
• Scientific Theories Have Been Thoroughly Tested

1.4 Evolution: The Unifying Theory of Biology

• Three Natural Processes Underlie Evolution
  Much of the Variability Among Organisms Is Inherited
  Natural Selection Tends to Preserve Genes That Help an Organism Survive and Reproduce

1.5 How Does Knowledge of Biology Illuminate Everyday Life?

Earth Watch: Why Preserve Biodiversity?

Case Study Revisited: Life on Earth—and Elsewhere?

Links to Life: The Life Around Us