Principles of Ecology


Ecology: the study of the interrelationships between living and _________ members of an area

Abiotic: ________________ things

Biotic: ____________ things

Ecosystem: the living and non-living things in an area

Population: the number of the _______ type of organisms in an area

Community: a ____________ of different organisms sharing the same environment

Habitat: a ______ where a particular organisms lives

Niche: a description of the _______ played by a species in a biological community

            Activity: Ecology Play, Habitat Rummy, Move over Rover



Food chain: a series of organisms beginning with producers/autotrophs (_______ plants) followed by herbivores (animals that eat ________), followed by an animal that eats herbivores, and ending in a carnivore.
            Activity: Food Scramble

Food web: the complex __________ of food interrelationships between plants and animals in the ecosystem.

  • Keystone species: a plant or animal that is so important that its loss would drastically ________ the population of many species in a habitat.

    Name a keystone species in our area:

Homework: Food Chain and Food Webs     


Trophic levels: Ecological Pyramid
            Level 1: Autotroph= Plants
            Level 2: Primary Consumer= Herbivore (eats ___________)
            Level 3: Secondary Consumer= Carnivore (eats _________)
            Level 4: Tertiary Consumer= Carnivore



The biomass of each level of the ecological pyramid is _______% less than the one below it! Only _____% of useable energy is transferred up to the next trophic level because so much is lost.


    1. Some of the food source many be __________ or indigestible.
    2. Energy may be expended catching the _________
    3. Energy is degraded through normal ______________ processes (Second Law of Thermodynamics).

What is missing from this ecological pyramid?

Detritis: Dead stuff like leaves and dead _____________.

Decomposers: Organisms that eat _________ stuff. Ex.

Health Issues:

Bio______________ of a toxin occurs when an organism absorbs and stores the toxin in its tissues

Biomagnification when the toxin becomes increasingly more concentrated higher up the ___________ chain.The best-known examples are the insecticide DDT and mercury.


Ecological Succession

Ecological succession is the process by which organisms occupy a site and gradually change environmental conditions by creating soil, shade, shelter, or increasing humidity

  • Primary Succession- occurs when a community begins to develop on a site previously ____________ by living organisms ex. island, new volcanic flow
    pioneer species- in primary succession, the species that _______ colonizes the new area
    -often microbes, mosses and lichens   
  • Secondary Succession- occurs when an ___________ community is disrupted and a new one subsequently ___________ at the site
    -disruption may be caused by natural catastrophe, human activity
    ____________ community- in either primary or secondary succession, when a community develops that resists further change
  • Aquatic Succession-process or succession taking place in a body of __________