2. Ecology Chapter 1 Section 3 OBJECTIVES: OBJECTIVES: 1. Explain how living organisms move energy through an ecosystem. 1. Explain how living organisms move energy through an ecosystem. 2. Explain how feeding relationships are important in an ecosystem. 2. Explain how feeding relationships are important in an ecosystem. 3. Explain how the amount of energy changes as it flows through an ecosystem. 3. Explain how the amount of energy changes as it flows through an ecosystem.

3. Living Things Capture and Release Energy Everything you do requires energy. Everything you do requires energy. The energy you use is chemical energy which comes from the food you eat. The energy you use is chemical energy which comes from the food you eat. The energy used can be released back to the environment as heat. The energy used can be released back to the environment as heat. Eventually the energy used must be replaced. Eventually the energy used must be replaced. This energy enters an ecosystem either directly or indirectly from the Sun. This energy enters an ecosystem either directly or indirectly from the Sun.

4. Producers A producer is an organism that captures energy and stores it in food as chemical energy. A producer is an organism that captures energy and stores it in food as chemical energy. They produce food for themselves and the rest of the ecosystem. They produce food for themselves and the rest of the ecosystem. Plants are the most common producers Plants are the most common producers

5. Consumers Consumers are organisms that get their energy by eating, or consuming, other organisms. Consumers are organisms that get their energy by eating, or consuming, other organisms. A primary consumer is the first link between producers and the rest of consumers (caterpillar) A primary consumer is the first link between producers and the rest of consumers (caterpillar) The secondary consumer feeds upon the primary consumer (Bird) The secondary consumer feeds upon the primary consumer (Bird) Consumers can be herbivores, carnivores, omnivores, or scavengers Consumers can be herbivores, carnivores, omnivores, or scavengers Scavengers feed on dead or decaying organisms. Scavengers feed on dead or decaying organisms.

6. Decomposers Decomposers break down dead plant and animal matter into simpler compounds. Decomposers break down dead plant and animal matter into simpler compounds. Decomposers can be fungi and bacteria Decomposers can be fungi and bacteria Decomposers release the last bit of energy from once living matter Decomposers release the last bit of energy from once living matter They also return raw materials back to the environment. They also return raw materials back to the environment.

7. Food Chain A food chain describes the relationship between a producer and a single chain of consumers. A food chain describes the relationship between a producer and a single chain of consumers. A food chain will only show one possible path of energy through an ecosystem. A food chain will only show one possible path of energy through an ecosystem.

8. Food Web A food web is a model of the feeding relationship between many consumers and producers in an ecosystem. A food web is a model of the feeding relationship between many consumers and producers in an ecosystem. It is many overlapping and interconnected food chains. It is many overlapping and interconnected food chains. A food web is a much better model of how energy might flow through an ecosystem. A food web is a much better model of how energy might flow through an ecosystem.

9. FOOD WEB

10. Energy Pyramid An energy pyramid shows the amount of energy available at each feeding level of an ecosystem An energy pyramid shows the amount of energy available at each feeding level of an ecosystem The first level is the producers, then primary consumers and then tertiary consumers. The first level is the producers, then primary consumers and then tertiary consumers. The largest amount of energy is available at the consumer level The largest amount of energy is available at the consumer level The amount of energy gets smaller and smaller from level to the next. The amount of energy gets smaller and smaller from level to the next.

11. Energy Pyramid