Populations and Communities

Populations and Communities

1. the living part of the earht is called a bioshphere

   • Biomes are the largest subunits of the bioshphere
     • Each Biome is defined in terms of its living organisms and their interactions with their enviroment

2. An ecosystem contains a dynamic but essentially self-sustaining and stable community of organisms interacting with each other and their non-living surroundings

   • The place within an ecosystem in which an individual organism lives is called a habitat

3. A population is a group of individuals of the same species that live in a particular area at any one time

4. A community consists of a group of populations of different interacting species living in an area at one time

5. An organisms total surroundings, including living,dead, and non-living components, make up its enviroment

   • Enviromental factors that result from the activities of living organisms are called biotic factors

6. A typical community has;

   • Autotrophs which manufacture their own food
     • herbivores that eat autotrophs
       • Secondary consumers that eat herbivores
         • tertiary consumers that eat secondary consumers
           • Decomposers that obtain nutrients by breaking down remains of dead organisims

7. Abiotic factors include

   • Climatic factors; light, temp.,wind
   • Edaphic factors; associated with soil such as; texture,pH, organic content
   • Topographic factors; angles and aspect of a slope