Lesson 3.2 - Food Chains

You know what a chain looks like. 

 

There are many kinds of chains. 

What is the same about these chains? 

Each link in the chain is connected to one link before it and one link after it.  Chains are used to connect things.  For example, you connect the anchor of a boat to the boat with a chain.  If you break a link in the chain, you break the connection between the boat and the anchor, losing the anchor.  One of the simple ways of communicating the energy pathways in an ecosystem is through food chains. 

Read Food Chains on page 242. Then, answer the following questions.

 

Question 1. What is a food chain?

Question 2. What is a producer?

Question 3. What is a consumer?

Question 4. What is a decomposer?

Question 5. What is the direction of the energy flow in a food chain?

Question 6. What do the decomposers return to the environment?

Question 7. What do you think will happen if one of the links in the food chain is broken?

 

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. What is a food chain?

A food chain is a model that shows how energy and matter pass from one organism to another in an ecosystem.  See the definition on page 312 in the textbook.

Question 2. What is a producer?

A producer is the organism at the bottom of the food chain that is able to produce its own food.  Any organism that can produce glucose through photosynthesis is a producer.

Question 3. What is a consumer?

A consumer is any organism that eats another organism.

Question 4. What is a decomposer?

A decomposer is any organism that breaks down any material from organisms that have died and are not eaten by consumers.  Earthworms, fungi, and bacteria are common decomposers.

Question 5. What is the direction of the energy flow in a food chain?

The energy flow in a food chain is always in one direction: from producer to consumer to decomposer.  Note that there may be many "links" of consumers; in the diagram the grouse is one link, the owl is the other link.

Question 6. What do the decomposers return to the environment?

Decomposers return chemical elements and chemical nutrients to the environment.  These recycled nutrients are used by plants.

Question 7. What do you think will happen if one of the links in the food chain is broken?

"If one of the links in the food chain is broken" means if one of the parts of the food chain disappeared, for example, if the grouse became extinct in the food chain at the bottom of page 242.  The grouse becoming extinct would be a serious problem for great horned owl; they would have no food. 

 


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