Ecology & Energy Flow Unit 2: “Live and Let Die” Ecology Chapters 3-6

Ecology Ecology—the study of interactions among organisms and between organisms and their environment.Ecology—the study of interactions among organisms and between organisms and their environment. The biosphere is the part of Earth in which life exists, including land, air, water, or atmosphere.The biosphere is the part of Earth in which life exists, including land, air, water, or atmosphere.

Abiotic vs. Biotic Biotic Factors — living things within an ecosystemBiotic Factors — living things within an ecosystem Abiotic Factors — nonliving things within an ecosystemAbiotic Factors — nonliving things within an ecosystem

Levels of Organization To understand relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual to the entire biosphere.

Levels of Organization Species—a group of similar organisms that can breed and produce fertile offspring.Species—a group of similar organisms that can breed and produce fertile offspring. Populations—groups of individuals that belong to the same species and live in the same area.Populations—groups of individuals that belong to the same species and live in the same area. Communities—assemblage of different populations that live together in a defined area.Communities—assemblage of different populations that live together in a defined area.

Levels of Organization Ecosystem—a collection of all the organisms (biotic factors) that live in a particular place, together with their physical environment (abiotic factors).Ecosystem—a collection of all the organisms (biotic factors) that live in a particular place, together with their physical environment (abiotic factors). Biome—a group of ecosystems that have the same climate and similar dominant communities.Biome—a group of ecosystems that have the same climate and similar dominant communities.

Energy Flow Living systems cannot function without constant energy.Living systems cannot function without constant energy. Energy flows through an ecosystem in one direction.Energy flows through an ecosystem in one direction. Sunlight is the main energy source for life.Sunlight is the main energy source for life.

Energy Flow Energy from the sun is utilized through photosynthesis.Energy from the sun is utilized through photosynthesis. Some organisms rely on other energy sources, such as energy stored in inorganic molecules.Some organisms rely on other energy sources, such as energy stored in inorganic molecules. Energy from chemical sources is utilized through chemosynthesis.Energy from chemical sources is utilized through chemosynthesis.

Producers and Consumers Producers—produce food in the ecosystem. These organisms are also called autotrophs, meaning they make their own food.Producers—produce food in the ecosystem. These organisms are also called autotrophs, meaning they make their own food. Consumers—consume food in the ecosystem. These organisms are also called heterotrophs, meaning they rely on other food sources (don’t make food).Consumers—consume food in the ecosystem. These organisms are also called heterotrophs, meaning they rely on other food sources (don’t make food).

Types of Consumers Herbivores—plant eatersHerbivores—plant eaters Carnivores—flesh (meat) eatersCarnivores—flesh (meat) eaters Omnivores—eat both plants and meatOmnivores—eat both plants and meat Detritivores—detritus (organic particles) eatersDetritivores—detritus (organic particles) eaters Decomposers—break down (decompose) organic materialDecomposers—break down (decompose) organic material

Food Chains, Food Webs, and Trophic Levels Food chains show the one way flow of energy in an ecosystem.Food chains show the one way flow of energy in an ecosystem. Food webs link all the food chains in an ecosystem together.Food webs link all the food chains in an ecosystem together. Each step in a food chain or food web is called a trophic level.Each step in a food chain or food web is called a trophic level.

Limiting Nutrients If a nutrient is in short supply, it will limit an organism’s growth.If a nutrient is in short supply, it will limit an organism’s growth. Limiting nutrient = a single scarce nutrient that is needed in an ecosystemLimiting nutrient = a single scarce nutrient that is needed in an ecosystem