Biology Notes

Biology Overview

• Definition of Biology: Biology is the study of life, understood as living organisms and their interactions.
• Focus: Primarily restricted to life on Earth.

The Science of Biology

• Biology Defined: Study of living organisms, interactions among organisms, and their environments.
• Definition of Science: Knowledge that encompasses general truths or laws, usually obtained through the scientific method.
• The Scientific Method: A research method with defined steps involving experiments and careful observation.

The Scientific Method

• Steps of the Scientific Method:
  • Introduction of a hypothesis.
  • If experimental data does not support the hypothesis, a new hypothesis can be proposed.

Types of Reasoning in Science

• Inductive Reasoning:
  • Uses observations to derive general conclusions.
  • Example: All organisms are composed of cells, hence cellular organization is a trait of life.
• Deductive Reasoning:
  • Applies general principles to predict specific outcomes.
  • Example: "All dogs are mammals. All mammals have kidneys. Therefore, all dogs have kidneys."

Scientific Reasoning

• Conclusions drawn from inductive reasoning can form premises for further inductive reasoning, fostering continued exploration.

Data in Biological Research

• Types of Data:
  • Qualitative: Descriptive observations (e.g., appearance, behavior).
  • Quantitative: Numerical measurements, often organized in tables/graphs.

Peer Review Process

• Importance of Peer Review: Advancements in science are typically documented through peer-reviewed literature, ensuring quality and credibility.
• Process: Scientists submit work to be evaluated blindly by experts in the field.
• Structure of Peer-Reviewed Papers:
  • Abstract, Introduction, Methods, Results, Discussion, Literature Cited.

Types of Literature in Science

• Primary Literature: Experts assess original research, confirming its significance, originality, and thoroughness.
• Secondary Literature: General reports on scientific work, including review articles and books.

Components of a Scientific Paper

• Titles, authors, affiliations, and sections such as Abstract, Introduction, Methods, Results, Discussion, and References.

Scientific Law vs. Theory

• Scientific Law: Describes predictable correlations between variables, sometimes expressed mathematically (e.g., Law of Gravity, Fick’s Law of Diffusion, J = -D∆C).
• Scientific Theory: Offers explanations of natural phenomena (e.g., theory of evolution, theory of relativity).

Basic vs. Applied Science

• Basic Science: Aims to expand knowledge without immediate applications.
• Applied Science: Utilizes scientific knowledge for specific practical purposes.

Properties of Life

• Characteristics of Living Organisms:
  • Order
  • Sensitivity to stimuli
  • Reproduction
  • Growth and development
  • Regulation
  • Homeostasis
  • Energy processing

Levels of Biological Organization

• Hierarchy of Life:
  • Atoms
  • Molecules
  • Macromolecules
  • Organelles
  • Cells
  • Tissues
  • Organs and Organ Systems
  • Organisms, Populations, Communities
  • Ecosystems
  • Biosphere

Interaction with the Environment

• Living organisms engage in matter and energy exchange with their surroundings, through processes such as nutrient cycling and energy transfer (e.g., sunlight to producers to consumers).

Domains of Life

• Three Domains: Bacteria, Archaea (both prokaryotes), Eukarya (eukaryotes including plants, animals, fungi).

Cellular Structures

• Prokaryotic Cells: Lack a nucleus and are simple in structure.
• Eukaryotic Cells: Possess a nucleus and complex organelles.

Multicellular Kingdoms

• Domain Eukarya consists of:
  • Kingdom Plantae
  • Kingdom Fungi
  • Kingdom Animalia
• Former Kingdom Protista: Now subdivided into various separate kingdoms.

Branches of Biological Study

• Disciplines:
  • Biomedical Research includes Physiology, Pharmacology, Biochemistry, and more.
  • Biological Research encompasses Botany, Ecology, Marine Biology, Genetics, and numerous other specialized fields.