Introduction to Life Science

• Adaptation

  • any structure, behavior, or internal process that allows a response to a stimulus.
• Evolution
- gradual accumulation of adaptations over time
• what two discoveries did Charles darwin made?

  natural selection , descent with modification
• Descent with Modification - each living species has descended, with changes, over time. This is a result of natural selection.
• Natural Selection - process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
• stimulus - any condition in the environment that requires an organism to adjust
• response - reaction to a stimulus
• homeostasis - stable level of internal conditions; any self-regulating process by which an organism tends to maintain stability while adjusting to conditions that are best for its survival
• unifying themes in the study of life
• unicellular - organisms is made up of one cell
• multicellular - organisms are made up of more than one cell
• metabolism - the chemical process by which a plant or animal uses food, water, etc., to grow and heal and make energy
• autotrophic - an organism that uses energy from the sun for photosynthesis to make its own food [usually plants]
• heterotrophic - an organism that ingests food to recieve energy [animals, fungi]
• meaning of DNA? - deoxyribonucleic acid
• DNA - contains the hereditary material; the biological blueprint
• growth - an increase in living material; refers to physical changes
• development - all changes that an organism undergoes in its lifetime; refers to functional or behavioral changes
• ecology - the study of the interactions between organisms and their environment
• Unifying themes in the study of life

  1. evolution & adaptation
  2. response & homeostasis
  3. organization
  4. energy
  5. reproduction, growth, & development
  6. interdependence of organisms
• abiotic factors

  non-living factors such as air, water, energy, soil, temperature, and minerals are needed for survival
• biotic factors


  includes all living factors here on earth
• theories in the origin of life

  1. special creation theory
  2. extraterrestrial origin
  3. spontaneous origin