Biology Study Notes

Definition of Biology

  • Study of living organisms and their diversity.
  • All living things share common features.

Characteristics of Life

  1. Cellular Organization: Unicellular or multicellular.
  2. Energy Utilization (Metabolism): Organisms require energy, mainly from the sun.
  3. Homeostasis: Ability to maintain stable internal conditions.
  4. Growth, Development, and Reproduction: All can grow and reproduce, through sexual or asexual means.
  5. Heredity: Genetic transmission via DNA.

Levels of Biological Organization

  • Cellular Level: Atoms, Molecules, Macromolecules, Organelles, Cells.
  • Organismal Level: Tissues, Organs, Organ Systems, Organisms.
  • Population to Ecosystem Level: Populations, Communities, Ecosystems, Biosphere.

Emergent Properties

  • Properties emerge from the interaction of system components (e.g., functional bicycles).

Structure and Function Relation

  • Structure provides insights into biological functions.

Cell Definition

  • Basic unit of life. Two forms: eukaryotic (with organelles) and prokaryotic (without organelles).

Biological Domains

  • Three domains based on characteristics:
    • Bacteria: Prokaryotic, unicellular, diverse functions.
    • Archaea: Prokaryotic, unicellular, extremophiles.
    • Eukarya: Eukaryotic, includes plants, fungi, and animals.

Evolution and Diversity

  • Evolution accounts for unity and diversity; organisms have common ancestors with accumulated differences.

Taxonomy

  • Classification of organisms based on similarities; involves Hierarchical classification: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Scientific Naming System

  • Binomial nomenclature (Genus + species) in Latin, italicized.