Introduction to Biology

Biology and Its Place in Science

• Biology is a science focused on life and its various aspects.
• The course covers the foundations of biology, including chemistry, cells, and metabolism.

Definition of Life

• The definition of life centers on the cell, which is the basic unit of organization for all life forms.
• Characteristics of life include:
  • Growing using raw materials and energy
  • Reproducing with the help of DNA as genetic material
  • Sensing and responding to changes in the external environment

Exclusion of Viruses from the Definition of Life

• Viruses do not fully meet the definition of "life" because they depend on cells for their reproduction.

Organization of Life

• Atoms and molecules organized in a particular way generate a living (biotic) cell capable of growth and reproduction.
• Properties of tissues and organs emerge from interactions among cells.
• Tissues and organs combine to form an organism, and multiple organisms give rise to populations, communities, and complex ecosystems.

Scientific Inquiry in Biology

• Biology, like all sciences, develops through the application of scientific inquiry.
• Scientific inquiry involves:
  • Asking questions
  • Forming hypotheses based on existing knowledge and observations
  • Testing hypotheses through experiments or observations
  • Analyzing data to determine whether the hypothesis is supported
• A nonscientific claim is a hypothesis that cannot be effectively tested by verifiable observations or experiments.