KEY CONCEPT Ecology is the study of the relationships among organisms and their environment.

Environmental levels of organization: An organism is an individual living thing (Ex: alligator) Organism

A population is a group of the same species living in one area. Organism

A community is a group of different species that live together in one area. Population Organism

An ecosystem includes all living and nonliving things in a given area. Community Population Organism

A biome is a major community of organisms--includes climate conditions Ecosystem Community Population Organism

Ecosystems include both biotic and abiotic factors. Biotic factors are living things. plants animals fungi bacteria plants

Abiotic factors are nonliving things. moisture temperature wind sunlight moisture sunlight

Biodiversity Biodiversity is the variety, of living things in an ecosystem. Importance of Biodiversity: Interrelationships Potential medicines An ecosystem will most likely remain stable if it has a high level of biodiversity

Ecosystem Energy Producers (autotrophs) make their own food. Consumers (heterotrophs) get their energy by eating other living or once-living things.

Consumers are not all alike. Herbivores eat only plants. Carnivores eat only animals. Omnivores eat both plants and animals. Decomposers eat dead organic matter. (fungi) They break down organic compounds into atoms carnivore decomposer

A food chain shows a sequence of feeding relationships A food chain shows a sequence of feeding relationships. If the grass (the producer) disappears, the cottontail (prey) has no food (dies), the hawk ( a predator) will lose its prey DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK

A food web shows a complex network of food chains

Trophic levels show flow of energy in a food chain (through nourishment/food) 90% of energy lost as it flows up the food chain. Carnivores Energy flow up the food chain Herbivores (primary consumers which are (anything that only eat plants) Producers (plants, anything that makes its own food)