Chapter 1 Intro to Bio

Introduction to Biology

• Focus: Principles of Biology, Cells & Genetics (BI 211)

• Chapter 1 Overview: Methods of science, living systems, and core concepts of biology.

Methods of Science in Biology

• Core Concepts Include:

  • Cellular organization and complexity.

  • Sensitivity and response to environment.

  • Growth, development, and reproduction.

  • Energy use and transformations.

  • Homeostasis and adaptation over time.

Understanding Complexity in Biology

• Why Biology Is Complicated:

  • Biological systems are constrained by physics and chemistry.

  • Biological systems are the most complex chemical systems on Earth.

  • All disciplines in biology have foundations in chemistry and physics, and also math.

Characteristics of Living Things

• Seven main characteristics shared by living things:

  1. Order/Organization/Complexity: Highly ordered structures.

  2. Response to Environment/Sensitivity: Ability to respond to stimuli (like light, touch).

  3. Reproduction: Capability to reproduce and create more of its kind.

  4. Energy Processing and Utilization: Organisms use and convert energy.

  5. Growth and Development: Genes control an organism’s growth.

  6. Regulation and Homeostasis: Maintenance of stable internal conditions.

  7. Evolutionary Adaptation: Changes in species over time adapting to environments.

Unifying Themes in Biology

• Biology can be structured into five unifying themes:

  1. Organization: Understanding structure and function relationships.

  2. Information: The flow, exchange, and storage of information in biological systems.

  3. Energy and Matter: Pathways and transformations crucial for life.

  4. Interactions: The importance of interactions at all organizational levels.

  5. Evolution: The processes of evolutionary change and adaptation.

Levels of Biological Organization

• Biological systems exhibit:

  • Hierarchical organization from atoms to the biosphere.

  • Emergent Properties: New characteristics emerge at each level of organization due to interactions among components.

Roles of Cells in Living Systems

• Basic Unit of Life:

  • The cell is the smallest unit that can perform all life functions.

  • Types of Cells:

    • Prokaryotic: No nucleus, simple structure (bacteria).

    • Eukaryotic: Membrane-bound organelles and nucleus.

Information Flow and Genetic Material

• The central dogma of biology explains the flow of genetic information:

  • DNA → RNA → Protein

  • Chromosomes contain DNA which encodes for proteins.

Energy and Matter in Biological Systems

• Life requires the transformation of:

  • Energy: Derived from the sun, utilized through photosynthesis (producers) or consumed from other organisms (consumers).

  • Matter: Essential chemicals for life processes.

Interactions in Biological Systems

• Interactions among system components are essential for functions across levels:

  • Example: Ecosystems exhibit interactions between organisms and their physical environments, which are regulated by feedback mechanisms.

Evolutionary Concepts

• Evolution involves the adaptation of species over time:

  • Natural Selection: Mechanism for descent with modification.

    • Observations supporting it include:

      • Variation in traits within populations.

      • Overproduction of offspring leading to competition.

      • Adaptation to environments offering survival advantages.

Classification of Life

• Biological diversity is classified into three domains:

  1. Bacteria (prokaryotic)

  2. Archaea (prokaryotic)

  3. Eukarya (including multicellular Organisms)

• Each species is identified with a two-part Latin name (e.g., Homo sapiens).

Geological Time and Evolution

• Evolutionary timelines divide Earth's history into major eons:

  • Hadean (4.6-3.8 BYA)

  • Archean (3.8-2.5 BYA): Origin of prokaryotes.

  • Proterozoic (2.5 BYA-545 MYA): Eukaryotic origins.

  • Phanerozoic (545 MYA-Present): Diversity of visible life.

Role of Plants in Evolution

• Plants have played a crucial role in Earth's ecosystem by contributing to oxygen production, biomass, and influencing climate changes.

Study Strategies

• After Lectures:

  • Learn vocabulary: Create flashcards.

  • Read textbook chapters and review notes.

  • Test self on material to solidify understanding.

  • Seek help early from instructors or tutors.