FOOD CHAINS & FOOD WEBS Revision sheet and Diagnostic Test Suggestion Teaching Objective: The aim of this lesson is to ensure students have a strong grasp on the key terms and concepts taught within this unit of study. Through providing a worksheet for student completion they will be able to identify what terms are most important as well as recognise where their possible weaknesses are. This could come before a diagnostic test is conducted so as to test the extent of student s knowledge being retained. An example of a diagnostic test as a suggestion is also provided below. Materials and Preparation: - Worksheet to be completed by students for revision purposes - Diagnostic Test FOOD CHAINS AND FOOD WEBS Worksheet Food Chain: A food chain is the series of organisms showing feeding relationships. A food chain almost always begins with a green (producer) which is eaten by an (consumer). The arrow means is eaten by, and shows the flow of matter and energy along the food chain. There are no in a food chain because they are so widespread and are not specific to just one food chain. Example of a Food Chain Grass(Producer) Grasshopper(1 st order Consumer) Kookaburra(2 nd order Consumer) Producer usually a green plant that produces its own food by First-order Consumer (also called the primary consumer) the organism that eats the Second-order Consumer (also called the secondary consumer) the organism that eats or derives nutrients from the Herbivore Carnivore an organism that obtains nutrients from an blood or flesh Omnivore an organism which eats both
Scavenger an consumer that eats animals (e.g. crab) Detritivore a consumer that obtains its nutrients from detritus Decomposer - an organism such as or fungi that breaks down dead organisms and their wastes Trophic Level A trophic level is each level in a food. Matter and energy are always lost as urine, faeces and heat energy at each trophic level. Food Web a of interrelated food chains in a given area Kingfisher Small fish Frog Tadpole Water Beetle Snail Algae Multiple Choice Questions 1. The arrow in a food chain means: A. eats B. hunts C. is eaten by 2. An example of a producer is a: A. human B. green plant C. herbivore 3. Another name for a plant eater is: A. a herbivore B. a first order consumer C. both of the above TEST FOOD CHAINS AND FOOD WEBS 4. Another name for the organism that eats the herbivore is the: A. secondary consumer B. primary consumer C. producer
5. Each level in a food chain is called the: A. consumer level B. trophic level C. production level 6. A consumer that eats already dead animals is the: A. scavenger B. parasite C. prey 7. Examples of decomposers are: A. bacteria B. fungi C. both of the above 8. An animal that eats both plant and animal matter is a: A. greedy animal B. omnivore C. herbivore 9. The organism that is never included in a food chain is the: A. decomposer B. herbivore C. producer 10. A network of interrelated food chains is: A. a food chain B. a food web C. an ecosystem True-False Questions 11. The first organism listed in a food chain is always the consumer. 12. The same organism in a food web can belong to different trophic levels. 13. Food chains are usually a maximum of about 5 or 6 organisms. 14. The organism at the top of a food web is the producer. 15. The size of organisms along a food chain tends to increase. Short Answer Questions 16. A carnivore gets its nourishment from meat. What else can a carnivore use for its nourishment? 17. Why is a decomposer never included in a food chain? 18. Why are food chains of a limited length? 19. What is the difference between plankton, phytoplankton and zooplankton? 20. Write an example of a food chain in a desert. 1.C 2.B 3.A 4.A 5.B 6.A 7.C 8.B 9.A 10.B 11.F 12.T 13.T 14.F 15.T TEST ANSWERS
16. Blood (e.g. leech) 17. Decomposers such as bacteria and fungi are everywhere in the environment. They are not specific to a food chain as would be a koala in a eucalypt forest. Hence, decomposers are not listed specifically in a food chain. 18. Matter is lost at each trophic level as faeces, urine etc. Energy is lost at each trophic level as heat. 19. Plankton means organisms that float in water. Phytoplankton are plants that float in water (e.g. seaweed). Zooplankton are animals that float in water (e.g. jellyfish). 20. Various answers. QUESTIONS Sort the following animals according to the way they get their food. The basic categories are forager, grazer, filter feeder, parasite, predator, and scavenger. clam blue whale flea sponge sheep piranha owl cow vulture bear louse gorilla striped hyena whale shark tiger crow tuna fish great white shark squirrel lion zebra leech monkey oyster Foragers Grazers
Filter Feeders Predators Scavengers Parasites