Chapter 2 Principles of Ecology Section 1: Organisms and Their Relationships Section 2: Flow of Energy in an Ecosystem Section 3: Cycling of Matter

2.2 Flow of Energy in an Ecosystem NUTRITION The ultimate source of energy is the SUN, which supplies the energy that fuels life.

Energy in an Ecosystem (Types of Niches) Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Energy in an Ecosystem (Types of Niches) The Producers Autotrophs - Organism that collects energy from sunlight or inorganic substances to produce food - Plant’s use the sun’s energy to manufacture food in a process called photosynthesis

Energy in an Ecosystem (Types of Niches) Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Energy in an Ecosystem (Types of Niches) The Consumers - Heterotrophs Organism that gets it energy requirements by consuming other organisms A lynx is a heterotroph.

2.2 Flow of Energy in an Ecosystem Chapter 2 2.2 Flow of Energy in an Ecosystem Primary Consumers: an organism that gets its energy from producers (plants); usually called herbivores Secondary Consumers: a consumer that gets its energy from other consumers; usually called carnivores Types of consumers Herbivores: only eats plants Carnivores: prey on other heterotrophs Omnivores: eat both plants and animals Scavengers: animals that feed on animals that have already died (ex: vultures, ants, beetles) Decomposers: organisms that break down and absorb nutrients from dead organisms (ex: fungi, bacteria)

Detritivores eat fragments of dead matter in an Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem ecosystem, and return nutrients to the soil, air, and water where the nutrients can be reused by organisms. Detritivores eat fragments of dead matter in an Fungus

Detritivores 2.2 Flow of Energy in an Ecosystem Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Detritivores

Food chains and food webs model the energy flow through an ecosystem. Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Models of Energy Flow Food chains and food webs model the energy flow through an ecosystem. Each step in a food chain or food web is called a trophic level.

Food Chains 2.2 Flow of Energy in an Ecosystem Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Food Chains A food chain is a simple model that shows how energy flows through an ecosystem. Arrows indicate the direction in which energy is transferred Usually 3-5 links; energy is lost in every transfer Energy is lost to the environment as HEAT

Food Chains 2.2 Flow of Energy in an Ecosystem Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Food Chains

Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Food Webs A food web is a model representing the many interconnected food chains and pathways in which energy flows through a group of organisms.

Food Webs 2.2 Flow of Energy in an Ecosystem Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Food Webs

Chapter 2 Principles of Ecology 2.2 Flow of Energy in an Ecosystem Ecological Pyramids A diagram that can show the relative amounts of energy, biomass, or numbers of organisms at each trophic level in an organism