1. Learning Objectives: to understand where organisms are able to survive on Earth to understand what an ecosystem is and what factors affect ecosystems. to understand the different feeding roles within an ecosystem and how energy is passed on between organisms to understand the different ways of representing organisms in an ecosystem- pyramids of numbers, biomass and energy

2. Sustainability Sustainability refers to the living in a way that ensures resources are available for a LONG time. Sustainable ecosystems are natural and undisturbed. They have characteristics that are constant over long periods of time. Unsustainable ecosystems are unnatural (artificial) and disturbed. Humans must take care of these ecosystems for them to survive (ex. water and fertilize plants in them)

3. Ecosystems An ecosystem consists of the living organisms in a region, their interactions with each other and with their non-living environment. Factors affecting ecosystems are: biotic: living organisms, their remains, products and wastes. abiotic: non-living physical and chemical components.

4. Earth’s Four Spheres Atmosphere: the layer of gases (mainly nitrogen and oxygen) surrounding the Earth. Acts as an insulator, regulating Earth’s surface temperature Blocks incoming solar radiation Lithosphere: Earth’s outer layer of solid rock. Consists of rocks, minerals and soil Hydrosphere: all of the water on and below Earth’s surface. Water is in solid, liquid and gas form- 97% is found in the oceans

5. Earth’s Four Spheres Biosphere: the regions within the 3 other spheres where life exists. Very thin compared to Earth’s size.

6. Levels of Organization Organism- a single living being (plant or animal) Population- a group of the same type of organisms living in an area Community- a number of different populations of organisms in an area Ecosystem- the community of organisms and their interactions with non-living substances in an area

7. Habitats A habitat is the place where an organism lives. There are two types of habitats: 1. Terrestrial – on land 2. Aquatic – in water

8. Producers create glucose (chemical energy) from light energy. They do not need to consume other organisms to get energy. Consumers are organisms which need to eat (consume) other organisms to get their energy. They cannot perform photosynthesis.

9. Feeding RoleDefinition HerbivoreAnimal which eats plants or other producers Ex: Rabbit CarnivoreAnimal which eats other animals Ex: Lion OmnivoreAnimal which eats both plants and animals Ex: Bear ScavengerAnimal which feeds on the remains of another organism Ex: Vulture DecomposerOrganism which feeds on and breaks down dead plant or animal matter Ex: Fungus, Earthworms

10. A food chain or food web shows how energy transfers between organisms and through an ecosystem by giving the order in which organisms are consumed. A food chain consists of a single pathway of energy transfer. The arrows show the direction energy is moving in from one organism to its consumer. Plants Insects Toads Snakes

11. A food web contains many different feeding relationships and energy transfer pathways.

12. Trophic level- is the feeding level, or position of the organism in the food chain. Ex: a producer is in the first trophic level Consumer level- is the position of the consumer in the food chain. Ex: an herbivore is the primary (first) consumer producers do not have a consumer level, because they do not consume other organisms to get energy.

13. The more complex the food web of an ecosystem, the more stable it is because there is more biodiversity. This means each organism can get its energy from a number of different sources. Thus, if one food source disappears, its predators have other prey to feed on.

14. Autotroph v. Heterotroph AutotrophHeterotroph Produce own Food YesNo Food Chain LevelPrimarySecondary and Tertiary ExamplesPlants, algae, some bacteria (producers) Herbivores, omnivores, carnivores, scavengers, and some bacteria (decomposers)

15. Food ChainFood Web  a specific pathway by which materials and energy move through an ecosystem  allow for the flow of energy through organisms (which all originates from the sun)  allow for the flow of matter through organisms  producers (autotrophs— green plants) capture some of the sun’s energy; they use 90 % of the sun’s energy to grow and live; the rest is passed onto consumers  consumers (heterotrophs) eat green plants (1 o ) and other consumers (2 o )  a network of interacting food chains operating in an ecosystem  it includes more organisms in an ecosystem than a food chain  shows competition