Chapter 2 2 Flow of Energy in an

Chapter 2. 2 – Flow of Energy in an Ecosystem

Chapter 2 Principles of Ecology 2. 2 Flow of Energy in an Ecosystem § Autotrophs § Organism that collects energy from sunlight or inorganic substances to produce food § Heterotrophs § Organism that gets it energy requirements by consuming other organisms A lynx is a heterotroph.

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

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.

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.

Level 4 Tertiary consumer Food chains § Feeding relationships Top carnivore Level 3 Secondary consumer all food chains start with energy from Carnivore the sun Level 2 Primary consumer u first level of all food chains is plants Herbivore u most food chains Level 1 Producer usually go up only 4 or 5 levels u all levels connect to Decomposers decomposers Bacteria u Regents Biology Sun Fungi

Food Chains in the water too. Regents Biology

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.

But what about decomposers? § Energy flows through but nutrients cycle u u nutrients must be recycled to be available for the next generation decomposers return nutrients to the soil after creatures die § fungi § bacteria Regents Biology n u t r i e n t s decomposers

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

Food chain pyramid § Loss of energy between levels of food chain u can feed fewer animals in each level Numbers 1 100, 000 1, 000, 000 Regents Biology

Vegetarians or Meat-eaters? ? § How many people can Earth support? If we are meat eaters? u If we are vegetarian? u more people can live on Earth Regents Biology fewer people can live on Earth