2 What is a Food Chain?All living things depend on each other to survive.Who do you depend on?
3 Food Chain Introduction All organisms on earth rely on each other because they are all members of food chains.A food chain shows the relationships among plants, animals, and other organisms in an ecosystem.Food chains outline who eats what.As each portion of the chain consumes the part before it in the chain, energy is transferred from one organism to the next.
4 Food Chain ContinuedIn a food chain “energy” sometimes refers to food and water, and other times refers to sunlight or other types of energy.Food chains maintain the balance of life on earth.If one element of a food chain disappears or increases greatly, the entire food chain will be affected.
5 How does a food chain work? All food chains begin with the sun.The sun provides energy for plants to grow and light required by people and other animals to function.
6 Trophic LevelAn organism’s position in a food chain is called its trophic level. (you can think of it as a food level)Producers are plants, comprising the first trophic level in a food chain.Producers are unique because they use the energy from the sun plus water and carbon dioxide to create food for themselves through a process called photosynthesis.
7 ProducersBecause they make food for themselves automatically, producers are called autotrophs.Plants are called “producers” because they produce the energy for all other members of a food chain.Examples of producers include flowers, grasses, and leaves.
8 Consumers Members of high food chain levels are called consumers. Consumers do exactly what their name implies they consume (eat).
9 ConsumersHerbivores : eat only plants or plant products. Examples of herbivores are mice, grasshoppers, rabbits, deer, beavers, moose, cows, and goats.
10 ConsumersCarnivores: eat only other animals. Examples of carnivores are foxes, frogs, snakes, spiders, and hawks.
11 ConsumersOmnivores: eat both plants and animals. People are omnivores because we eat both plants (like fruits and vegetables) and animals (like chicken or beef). Other examples of omnivores are bears, monkeys, and turtles .
12 3 Different levels of Consumer Primary consumers are those that feed directly from producers. Because they only eat plants they are herbivores. (Squirrel, elk, grasshoppers)Secondary consumers feed on primary consumers. Secondary consumers can be carnivores or omnivores depending on their environment. (birds, frogs, cats)Tertiary consumers eat secondary consumers, and can be carnivores or omnivores. (wolves, and owls)
13 Decomposers Decomposers are the last link in the food chain. As each member of the food chain dies, decomposers eat it, break down “dead stuff”, and return the nutrients to the soil.
14 Creating your own food chain model Begin by cutting out the five organisms on your sheet.Glue each picture to the appropriate tube. (Owl largest, Snake, mouse, grasshopper, and grass on the smallest).Place tubes back together.
15 The Food Chain StoryThere are many different food chains on earth. This one features the Great horned owl at the top. Other food chains work just like this one but with other plants and animals.All food chains begin when the energy of the sun reaches the earth. The energy carried in the sun’s light, along with water and carbon dioxide, allows plants to grow, like the grass on your smallest tube.
16 Story continuedThe grass is eaten by primary consumers, such as the grasshopper on your second tube. (Students will now make grasshopper eat grass)All primary consumers are herbivores that eat only plants.
17 Story continuedThe grasshopper is then eaten by a mouse(on the next largest tube), a secondary consumer. (students now have mouse eat grasshopper)Secondary consumers can be either carnivores or omnivores, but not herbivores.Carnivores eat only meat and omnivores eat both meat and plants.
18 Story continuedNext, the mouse is eaten by the snake. (students now have snake eat mouse).The snake can be considered either a secondary or tertiary consumer. If it were at the top of the food chain it would be tertiary, but since we know it is not we will consider it a secondary consumer.
19 Story continuedFinally, the Great horned owl eats the snake. (students will now have the owl eat the snake).The owl is a tertiary consumer and resides at the top of the food chain (it isn’t eaten by another animal in our food chain).
20 Story continuedEventually, the owl will die and its body will be decomposed by bacteria and fungi.Through decomposition, nutrients from the owls body will go back into the soil and provide nutrients that will allow many new plants (producers) to grow, beginning the cycle again.
21 Your food chain storyIn your journal retell the food chain story you just acted out with the tubes.Use vocabulary words like primary consumers, secondary consumers, tertiary consumers, producers, carnivores, herbivores, and omnivores. Plus any others you would like to use.Draw an illustration of the food chain story you just acted out.