Honolulu Zoo Society : Interdependence - What's for Lunch?

Food Chains and Food Webs

Topic Overview

Begin the Lesson

A food chain shows how plants and animals get energy from each other. Some animals like to eat plants and so they eat plants. Some animals eat other animals. There are some animals that eat plants and other animals. This process is called a food chain.  In this video, students will see a food chain in action. Much emphasis is placed on the predators and prey.


Whole Class Introduction to the Lesson

You will need at least one computer with Internet connectivity and a projection device, a classroom with more than one computer, or access to a computer lab.  This introduction will take approximately 10 minutes to complete. Before watching the video, ask students why the sun is important to plants and animals. Then ask students why plants are important to animals, including humans. Then show students this video: http://www.youtube.com/watch?v=3Bn7wdCP2v4.

Sample Questions:

  • What is a food chain? What examples did you see in the video?
  • Why is grass important in the Serengeti Desert?
  • Imagine you were a predator. What would your day be like?
  • Imagine you were prey. What would your day be like?

As part of the introduction, you may want to review some of the glossary terms in advance of students going online. At this point you can launch the WebLesson as whole-class activity using a projection device, or you can assign students to work individually or in teams in a computer lab.



WebLesson Sites
Grass gets energy from the sun. Cows like to eat grass. Milk comes from a cow and people like to drink milk. The grass, cows, and people is an example of a food chain. Without the cows, people would not have milk. Without grass, cows would not get energy to make milk. Every part of a food chain is important for the cycle of life.
You visited the zoo and watched a frog jumping in a pond. The frog liked bugs. You noticed that the frog really liked small flies. You didn’t like the small flies and you wondered what would happen if you could make all the flies go away. Would you break the food chain?
Lesson Pages
Working on the Food Chain
Rich Media
Conclusion & Project
What we eat for lunch or dinner is part of a food chain. A food chain shows how plants and animals get energy from each other. It starts with energy from the sun. A food chain often ends with a predator or an omnivore like humans. Each plant and animals in the chain is important.

Many food chains make up a food web. Predators at the end of the food chain die and are eaten by decomposers, which provide soil for producers. Whether it is a food chain or food web, plants and animals need each other. They depend on each other for survival.
Remember your trip to the zoo, where you watched the frogs eating small flies? What would happen to the food chain if you took out all those small flies that you don't like but the frogs liked to eat?
carnivore - an animal that likes to eat other animals
consumer - an animal that eats other plants and animals
decomposer - an organism that eats dead plants and animals; recycles decomposed parts back into the soil
dwindle - to decrease or become less
food chain - the order of plants and animals getting energy from the sun and feeding on each other
harness - to control to make energy
herbivore - an animal that likes to eat plants
omnivore - an animal that likes to eat plants and animals
parasite - an organism that grows or feeds on an animal; a parasite takes away from the animal and can cause disease
photosynthesis - a process used by plants to convert light energy, normally from the sun, into chemical energy that can be used to fuel the plant
predator - An animal that hunts and kills other animals.
prey - An animal that is eaten by another animal.
producer - a plant that makes its own food from energy from the sun