Food Webs Lessons

Food Chains and Food Webs

by Erin Hannan

​What we will learn about...

• ​difference between food chains and food webs

• ​producers

• ​consumers

• ​decomposers

• ​how food chains interact to become food webs

Open Ended

What is the difference between a food web and a food chain? 

​Food Chains

• ​models that show the path that energy takes throughout an ecosystem

• ​more simply: who eats whom

• ​energy is transferred between organisms when they are eaten

​Food Webs

• ​food chains interact to form food webs

• ​organisms are usually part of more than one food chain - have more than one preadtor or prey

• ​food webs show all feeding relationships in an ecosystem

Multiple Choice

The food chain is--

• The movement of water from the surface to the atmosphere.

• The path of food energy from one organism to another.

• The ranking of organisms by size in an ecosystem.

• A list of food that consumers will eat in an ecosystem.

​Producer, consumer, or decomposer?

• ​organisms are one of the three in each food chain

• ​food chains always start with a producer

• ​consumers can be primary, secondary, or tertiary

• ​decomposers are really the 'final consumers'

​Producer

• ​an organism that produces their own food/energy

• ​starts the food chains

• ​mostly plant life

​Consumers

• ​organisms that gains energy by consuming other organisms

• ​Primary = organisms that eat producers

• ​Secondary = organisms that eat primary consumers

• ​Tertiary = organisms that eat secondary organisms

• ​Those at the top of the food chain (i.e. have no predators) are called apex predators

​Decomposers

• ​organisms that gain energy by breaking down dead material (plants or animals)

• ​generally bacteria or fungi

• ​put back nutrients into the soil to help producers grow

Multiple Choice

Who is the producer in this food chain? 

• Grass
• Grasshopper
• Mouse
• Ow

Multiple Choice

Which of these organisms would receive energy from the snake?

• Plant
• Rabbit
• Mouse
• Hawk

Multiple Choice

Who does the owl get energy from? 

• Grass
• Grasshopper
• Mouse
• Ow