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Education 214

Lesson Plan for Park Street Intermediate

April 3, 2009

Food Chains and Food Webs

GRADE LEVEL INDICATORS:

·  Subject: Science

·  Grade Level: 5th Grade

o  Benchmark: Life Sciences: Diversity and Interdependence of Life

§  Grade Level Indicators:

·  1. Describe the role of producers in the transfer of energy entering ecosystems as sunlight to chemical energy through photosynthesis

·  2. Explain how almost all kinds of animals’ food can be traced back to plants.

·  3. Trace the organization of simple food chains and food webs (e.g., producers, herbivores, carnivores, omnivores, and decomposers).

·  4. Summarize that organisms can only survive in ecosystems in which their needs can be met (e.g., food, water, shelter, air, carrying capacity and waste disposal). The world has different ecosystems and distinct ecosystems support the lives of different types of organisms.

·  5. Support how an organism’s pattern of behavior are related tot eh nature of that organism’s ecosystem, including the kinds and numbers of other organisms present, the availability of food and resources, and the changing physical characteristics of the ecosystem.

INSTRUCTIONAL OBJECTIVES:

·  Students will participate in a discussion of food chains and food webs.

·  Students will participate in a discussion of producers and consumers.

·  Students will participate in the analysis of a basic food chain.

·  Students will participate in the analysis of a food web.

·  Students will participate in a game focused on the concepts of food webs.

MATERIALS:

·  Dry Erase Board

·  Dry Erase Markers

·  Consumers/Producers Poster

·  Food Chain Poster

·  Food Web Poster

·  Animal Picture Nametags (25) ( 5 cattails, 1 mouse, 1 muskrat, 10 shellfish, 5 minnows, 2 bass, 1 eagle, 1 person)

·  32 construction paper tokens

·  Copies of The Mystery of Sandy Bottom Creek

PROCEDURE:

1.  Discussion

  1. Ask the students: What do you know about food chains?
  2. Record the students’ answers on the dry erase board.
  3. Ask the students: What do you know about food webs?
  4. Record the students’ answers on the dry erase board.

2.  Consumers/Producers

  1. Display the Consumers/Producers Poster.
  2. Ask the students: What is a producer?
  3. Provide students with the definition provided on the poster: Plants are called producers because they are able to use light energy from the sun to produce food (sugar) from carbon dioxide and water.
  4. Ask the students: What is a consumer?
  5. Provide students with the definition provided on the poster: Consumers cannot make their own food so they must eat plants and/or other animals.
  6. Ask the students: What is an herbivore?
  7. Provide students with the definition provided on the poster: Herbivores eat only plants.
  8. Ask the students: What is a carnivore?
  9. Provide students with the definition provided on the poster: Carnivores eat other animals. Carnivores that eat only herbivores are called secondary consumers. Carnivores that eat other carnivores are called tertiary consumers.
  10. Ask the students: What is an omnivore?
  11. Provide the students with the definition provided on the poster: Omnivores eat both plants and animals.

3.  Food Chain

  1. Display the Food Chain Poster.
  2. Explain that the poster operates in the following way:
  3. The grass produces its own food using the sun.
  4. The giraffe eats the grass.
  5. The lion eats the giraffe.
  6. Ask students if they have any questions about food chains.

4.  Food Web

  1. Display the food web poster.
  2. Explain that the poster works in the following way:
  3. The grass produces its own food using the sun.
  4. The caterpillar, the snail, and the rabbit eat the grass.
  5. The iguana eats the caterpillar.
  6. The bird eats the caterpillar, the snail, and the grass.
  7. The bald eagle eats the iguana, the bird, and the rabbit.

5.  Game

  1. Provide students with the following background information: (write the information on the dry erase board)
  2. Bioaccumulation – process by which pollutants build up in the environment through the food web
  3. Pesticide – any chemical preparation used to control populations of organisms including plants and animals, perceived to be injurious
  4. Toxin – any metabolic product of a living organism that is poisonous to other organisms, or any substance damaging to living things
  5. Bioaccumulation example: plants are sprayed with a pesticide. Insects eat the plants and ingest the pesticide. Some die, other are eaten before the pesticide kills them. A bird or other animal eats several insects, ingesting the pesticide. The consumer’s body now contains a quantity of pesticide equal to the amount taken in by an insect multiplied by the number of insects and plants it ate. A predator now eats a few of the secondary consumers, and the pesticide is further ingested in its body.
  6. Read The Mystery of Sandy Bottom Creek to the class. (Can give copies to allow them to follow along)
  7. Draw a map of the situation in the story as you read.
  8. Ask students if they can solve the mystery. How did the boy become ill? Could it be from something he ate? Hint: There is a man in New Port City who earns his living by catching fish in the Johnstown River and selling them to markets throughout the region.
  9. Explain that each student will represent a component of the King’s Folly marsh ecosystem. Pass out the animal nametags to each student (5 cattail plants, 1 muskrat, 1 mouse, 10 shellfish, 5 minnows, 2 bass, 1 eagle, 1 person)
  10. Start at the “bottom” of the food web. Remind students that they know the pesticide did get into the water that flows through the Marsh on its way to New Port City.
  11. Ask the cattails what they need to survive (soil, water, sunlight, air). Tell them that as cattails take up water, they are also taking in the pesticide. Give each cattail three construction paper tokens to represent the pesticide.
  12. Ask which of the animals would eat the cattails. Cattails that are eaten by the muskrat should give their construction paper tokens to the muskrat. Cattails that are eaten by the mouse should give their construction paper tokens to the mouse. How many tokens does each of these animals have now?
  13. Ask who would eat these animals. Have the muskrat and mouse give all of their paper tokens to the eagle. This is enough to kill the eagle.
  14. Give each shellfish 2 tokens. Explain that shellfish feed by filtering tiny bits of plant and animal material out of the water.
  15. Ask which of the remaining animals would eat these shellfish. Have the minnows eat the shellfish and take their pesticide tokens.
  16. Next, have the bass eat the minnows and take their tokens.
  17. The person then eats the bass and takes the tokens from the bass. Ask if this is enough to make a person ill.
  18. Explain that this is a simplified demonstration of a natural process called bioaccumulation. Substances that accumulate in organisms work their way through the food web.
  19. Ask the students to review the process by describing what happened.
  20. Ask the students: How did the people get sick?
  21. Record answers on the board.
  22. Answer: Bioaccumulation of the pesticide caused the sickness. The sick people ate fish caught in the Johnstown River. These fish fed in the marsh before they moved downstream. Some of the contaminated fish were sold in New Port City.
  23. Ask students: Why didn’t the people in Cedarville get sick?
  24. Record answers on the board.
  25. Answer: Cedarville kids fished and swam in Sandy Bottom Creek north of town, upstream from the runoff from Cedarville Farms. King’s Folly Marsh ran downstream from the farms.
  26. Ask students: Why didn’t the water test show dangerous levels of pollutants?
  27. Record answers on the board.
  28. Answer: The marsh filtered out some of the pollutants, so the water flowed on to the Johnstown River was not badly contaminated. The marsh wasn’t able to filter out all of the pesticide, however, so the chain of bioaccumulation began.
  29. Ask students: When pollutants wash away, are they really away? Is the problem gone? Is the presence of the marsh part of the problem?
  30. Record answers on the board.
  31. Answer: No! Benefits of the marsh: helps filter pollutants; provide food and cover for valuable materials

6.  Closing Questions

  1. Ask students if they have any further questions.

ACCOMMODATIONS:

-  Based on student participation, more prompting questions may need to be posed to obtain prior knowledge of food chains and food webs.

-  Number of students will affect which animals are utilized in the game. May need to utilize teachers as a part of the game.

-  If a student is reluctant to participate in the game, provide them with a beginning role that is “eaten” near the beginning.

-  Time will be a factor and will need to be monitored during discussion of producers/consumers, food chains, and food webs. Sufficient time needs to be provided for the game.