 All the organisms living in an area and the nonliving features of their environment  Biotic – living  Abiotic – nonliving

 Organism – single living creature  Population - All the organisms in an ecosystem that belong to the same species (biotic)  Community - All the populations in an ecosystem (biotic)

Organism Population Community Ecosystem

 Habitat - The place in which an organism lives  Niche - The specific role that an organism plays in its ecosystem  Competition - Limits population size

 Life in an ecosystem requires a source of energy.  Producers provide energy for other organisms in an ecosystem.  Producers get their energy from non-living resources. (The SUN)  Producers are also called autotrophs because they make their own food.

 Consumers  organisms that get their energy by eating other living or once-living resources.  Also called heterotrophs … they feed off of different things.  Omnivores  Eat both plants and animals

 A food chain follows the connection between one producer & a single chain of consumers within an ecosystem.  A food web emphasizes complicated feeding relationships & energy flow in an ecosystem.

 Energy pyramids compare energy used by producers and other organisms on trophic levels.  Ten Percent Rule - Only 10% of the energy at each tier is transferred from one trophic level to the next.

energy transferred energy lost  Energy pyramids compare energy used by producers and other organisms on trophic levels. Between each tier of an energy pyramid, up to 90% of the energy is lost into the atmosphere as HEAT. Only 10% of the energy at each tier is transferred from one trophic level to the next.

 Biomass Pyramid - is a measure of the total dry mass of organisms in a given area. tertiary consumers secondary consumers primary consumers producers 75 g/m2 150g/m2 675g/m2 2000g/m2 producers 2000g/m2

 A pyramid of numbers shows the numbers of individual organisms at each trophic level in an ecosystem. tertiary consumers secondary consumers primary consumers producers ,000 5,000,000 A vast number of producers are required to support even a few top level consumers.

1.Energy Flows through an Ecosystem and Nutrients Cycle in an Ecosystem. 2. In an Ecosystem the Three Primary Nutrient Cycles: A. The Water Cycle B. The Carbon Cycle C. The Nitrogen Cycle

 The Water Cycle Usually Consists of the following steps: 1. EVAPORATION 2. TRANSPIRATION 3. CONDENSATION 4. PRECIPITATION 5. RUN OFF (or RETURN)

 EVAPORATION from lakes, rivers, and oceans.  TRANSPIRATION from plants and trees.  CONDENSATION – Cloud Formation  PRECIPITATION – Rain, Snow, Sleet, Hail  RUN OFF, or RETURNED back into the Cycle.

 Photosynthesis – Carbon out of the air  Cellular respiration – Carbon into the air  Burning Fossil fuels – Carbon into the air.

 Competition occurs when two organisms fight for the same limited resource.  Intraspecific competition  Same species  Interspecific competition  Different species

 There are three major types of symbiotic relationships.  Mutualism: both organisms benefit  Commensalism: one organism benefits, the other is unharmed  Parasitism: one organism benefits, the other is harmed  ectoparasites (such as leeches)  endoparasites (such as hookworms)

 Primary Succession - initial development of plant or animal communities in an area where no soil initially exists (such as caused by a lava flow following volcanic eruption or severe landslide that covered the land).

 new inhabitants replace the previous community of plants and animals that has been disrupted or disturbed by an event (e.g. forest fire).

 Taiga  Deciduous forest  Tropical rain forest  Desert  Tundra  Grassland

 A cool forest biome of conifers in the upper Northern Hemisphere – Most of Russia is covered in this.

 A forest biome with many kinds of trees that lose their leaves each autumn

 A hot, humid biome near the equator, with much rainfall and a wide variety of life.  The closer you get to the equator the warmer and wetter it gets

 A sandy or rocky biome, with little precipitation and little plant life  Key point: Deserts are about precipitation not temperature.

 A cold biome of the far north; the ground is frozen even in summer  Know! – Permafrost – frozen ground year round.

 A biome where grasses, not trees, are the main plant life. Prairies are one kind of grassland region.  Largest biome in US!!!