Unit A

• SPECIES


  LIVING THINGS OF THE SAME KIND THAT ARE ABLE TO REPRODUCE SUCCESSFULLY
• BIOLOGICAL DIVERSITY


  THE VARIETY OF SPECIES AND ECOSYSTEMS ON THE EARTH AND THE ECOLOGICAL PROCESSES OF WHICH THEY ARE A PART
• ECOSYSTEM


  A PARTICULAR ENVIRONMENT WHERE LIVING THINGS INTERACT WITH OTHERS LIVING THINGS AND NON-LIVING THINGS
• POPULATION


  GROUP OF INDIVIDUALS OF THE SAME SPECIES LIVING IN AN AREA
• COMMUNITY


  A GROUP OF POPULATIONS OF DIFFERENT SPECIES LIVING IN THE SAME AREA
• SYMBIOSIS


  THE RELATIONSHIP BETWEEN TWO DIFFERENT SPECIES
• COMMENSALISM


  THE RELATIONSHIP BETWEEN SPECIES IN WHICH ONE SPECIES BENEFITS, AND THE OTHER SPECIES NEITHER BENEFITS NOR IS HARMED
• MUTUALISM

  THE RELATIONSHIP BETWEEN SPECIES IN WHICH BOTH SPECIES BENEFIT
• PARASITISM

  THE RELATIONSHIP BETWEEN SPECIES IN WHICH ONE SPECIES BENEFITS AND THE OTHER SPECIES IS HARMED
• INTERSPECIES COMPETITION


  TWO OR MORE SPECIES USING THE SAME LIMITED SOURCE
• NICHE

  THE ROLE OF AN ORGANISM OR SPECIES IN AN ECOSYSTEM, INCLUDING WHERE IT LIVES, WHAT IT EATS , HOW IT REPRODUCES, AND HOW IT INTERACTS WITH OTHER LIVING THINGS AND NON-LIVING THINGS
• RESOURCE PARTITIONING

  DIVISION OF A RESOURCE AMONG TWO OR MORE COEXISTING SPECIES
• VARIABILITY

  VARIATIONS WITHIN A SPECIES
• NATURAL SELECTION


  A PROCESS IN WHICH THE ENVIRONMENT "SELECTS WHICH INDIVIDUALS WILL SURVIVE AND REPRODUCE