13.4 Food Chains And Food Webs KEY CONCEPT Food chains and food webs model the flow of energy in an ecosystem. Collect HW: 13.4 Pages # 408-411 5 Facts/Page
13.4 Food Chains And Food Webs Assessment 13.3 1. Few producers live deep below a lake’s surface, suggest an explanation for this pattern. 2. Could producers survive without consumers? Explain, why or why not. 3. What are the two processes used by producers to obtain energy?
13.4 Food Chains And Food Webs A food chain is a model that shows a sequence of feeding relationships. • A food chain links species by their feeding relationships. • A food chain follows the connection between one producer and a single chain of consumers within an ecosystem. GRAMA GRASS DESERT COTTONTAIL HARRIS’S HAWK
13.4 Food Chains And Food Webs • Consumers are not all alike. – Herbivores eat only plants. – Carnivores eat only animals. – Omnivores eat both plants and animals. – Detritivores eat dead organic matter. – Decomposers are detritivores that break down organic matter into simpler compounds. carnivore decomposer
13.4 Food Chains And Food Webs • Specialists are consumers that primarily eat one specific organism or a very small number of organisms. • Generalists are consumers that have a varying diet.
13.4 Food Chains And Food Webs • Trophic levels are the nourishment levels in a food chain. – Primary consumers: herbivores that eat producers. – Secondary consumers: carnivores that eat herbivores. – Tertiary consumers: carnivores that eat secondary consumers. – Omnivores: eat both plants and animals, may be listed at different trophic levels in different food chains. – (how many trophic levels are below?) 4
13.4 Food Chains And Food Webs A food web shows a complex network of feeding relationships. • An organism may have multiple feeding relationships in an ecosystem. A food web emphasizes complicated feeding relationships and energy flow in an ecosystem.
13.4 Food Chains And Food Webs Energy Energy Systems • Energy is lost as it moves from one organisms to another. Typically 10% 10 pounds of rats = 1 pound of snake or coyote
13.4 Food Chains And412-416 5 Facts/PageHW: 13.5 Pages # Food Webs13.4 Study Guide Review1. Herbivore 2. Decomposer3. Detritivore 4. Omnivore5. Food Chain 6. Trophic Level7. Food Web8. The first consumer is called a ___9. How is the food web different from a food chain?10. What happens to energy at each link in a food web? Quiz next time!!!
13.4 Food Chains And412-416 5 Facts/PageHW: 13.5 Pages # Food WebsClassworkDefine:HerbivoresDecomposersDetritivoresOmnivoresStudy Guide 13.4 P. 139 #1-13Reader 13.4 P. 231 # 1-4 Quiz is next!!!