Biology Is the Study of Life

1
Biology Is the Study of Life

• Living things,
• from simple
• cells to
• complex
• multicellular
• organisms,
• share common
• features and
• characteristics

2
Characteristics of Life

• Organization
• Metabolism
• Acquisition and Utilization of Energy
• Acquisition and Utilization of Matter
• Homeostasis
• Response to Environmental Stimuli
• Evolution
• Genetic Transmission
• Reproduction
• Development, Growth, Maintenance, Repair

3
The Unity In Lifes Diversity Theme is Evolution

• The vast diversity of life forms on the planet
  have evolved to their present form from a common
  ancestor.
• Nature selects successful organisms who survive
  to reproductive maturity, therefore, differential
  reproduction ensures survival of the fittest,
  best adapted species.
• Living things are interactive through the
  transfer of energy and interconnected through
  cycles of matter.

4
Organizational Hierarchy

• Atoms to molecules
• Molecules to macromolecules
• Macromolecules to organelles
• Organelles to cell (unicellular or multicellular
  organisms)
• Cells (multicellular) to tissue
• Tissues to organs
• Organs to systems
• Systems to organisms
• Like organisms compose a species
• Members of the same species compose a population
• Different population compose a community
• Communities compose ecosystems
• Ecosystems compose biomes
• Biomes compose the biosphere

5
Organisms Maintain Order and Organization

• According to the Second Law of Thermodynamics,
  Entropy, which is disorder, is always increasing
  in the universe.
• Living organisms use energy and macromolecules
  from food to maintain organization through
  metabolism.

6
Energy Flow and Cycles of Matter Form
Interacting and Interconnecting Webs

• Producers transform energy and use it to
  chemically bond molecules to produce food.
• Both producers and consumers transform the energy
  in food and use it and the molecules in food to
  maintain organization and do work.
• -Decomposers recycle matter
• Matter is recycled, energy is not.
• Metabolism- sum total of all of the chemical
  reactions that maintain an organism functioning.

7
Homeostasis Maintenance of Optimal Ranges and
Conditions

• Internal consistency of temperature, pH,
  concentrations of sugars, electrolytes, etc.
• Along with optimal conditions, for metabolic
  reactions to occur the following are necessary
• Enzymes
• Energy

8
Feedback Loops Establish Homeostasis
9
Response to Environmental Stimuli

• Response to internal environmental stimuli by
  feedback loops to maintain homeostasis
• -short range responses are mediated by the
  nervous system.
• -long range responses are mediated by the
  endocrine system.
• Response to external environmental stimuli is
  also necessary to maintain homeostasis, as well
  as for survival.
• Nature selects the fittest for survival
  Evolution

• Change in pigmentation to camouflage ensures
  survival.
• Organisms must respond to environmental
  stimuli in order to survive, as well as to
  maintain internal homeostatic balance.
• Adaptations are features that allow organisms to
  survive in their environment.

10
Reproduction and Genetic Transmission

• Genetic transmission ensures the inheritance of
  traits that are successful for survival.
• Inheritance, from parent to offspring, through
  genes, which are contained on the DNA of the
  chromosomes and in some cases the mitochondria.
  In some viruses the genes are on the RNA.
• Expression of genetic traits provide instructions
  for development, growth, metabolism, etc.
• Members of a species have the same kind and
  number of chromosomes

11
Development, Growth, Maintenance, and Repair

• Living organisms must put their genes into action
  through the development, growth, and maintenance
  of their bodys organ systems to fulfill their
  roles as successful members of their species,
  which is to reproduce effectively.

12
The unique characteristics of life are a common
theme in both simple organisms and complex
organisms, whether unicellular or multicellular,
whether prokaryotic or eukaryotic.