Match Each of These Words to the Descriptions Below

HELP

1In a food chain, there are producers (plants), primaryconsumers (that eat the plants) and secondary consumers(that eat the primary consumers).

Match each of these words to the descriptions below.

APlants need this from the Sun to make food.

BPlants are eaten by this type of consumer.

CHerbivores are eaten by this type of consumer.

DThese animals only eat other animals.

EThese animals only eat plants.

FThese animals eat both animals and plants.

GAnother name for plants.

2Look at this food chain.

aCopy the food chain and connect the boxes with arrows.

bWhich organism is the producer?

cWhich organism is the primary consumer?

dWhat would happen to the number of eagles if a disease halvedthe number of small birds they could eat?

© Harcourt Education Ltd 2003 Catalyst 1

This worksheet may have been altered from the original on the CD-ROM.

CORE

3Here are three food chains:

aWhat do the arrows in each food chain represent?

bYou are going to construct a food web from the three food chains above.

• Start by writing the names of the three producers along thebottom of your page.
• Draw an arrow up from each producer, and write the namesof the primary consumers above these arrows.
• Continue upwards, linking the three food chains togetherinto a single food web.

Eagles are predators in some food chains but their eggs areprey in other food chains, because they are eaten by foxes.

Foxes also eat rabbits. Mice also eat grass.

• Add this information to your food web.

© Harcourt Education Ltd 2003 Catalyst 1

This worksheet may have been altered from the original on the CD-ROM.

EXTENSION

4Look at the food web you constructed in question 3.

aExplain why foxes are sometimes shot in areas where eagleslive.

bThe UK had an enormous over-population of rabbits in the1960s. A disease called myxomatosis was developed to kill lotsof rabbits and control their population. What effect mightintroducing myxomatosis have had on the number of eagles?Explain how you arrived at your answer.

cHow might clearing all the local streams and ponds of most ofthe waterweed change the numbers of foxes in the area?Explain your answer.

5aExplain what the term ‘interdependence’ means to you.

bIllustrate how interdependence works by describing thepossible effects of adding owls to the food web you constructedin question 3. Say why these effects would happen.

© Harcourt Education Ltd 2003 Catalyst 1

This worksheet may have been altered from the original on the CD-ROM.