Science- Unit B, Chapter 4

At which stage of primary succession do lichens start to grow on exposed rock?

• pioneer-plant stage

• mossy stage

• grassy stage

• climax- community stage

During the second stage of primary succession,

• lichens grow on rocks

• alders and willows grow

• wildfires often happen

• mosses take over

Secondary succession might happen after-

• primary succession

• a harsh winter

• a forest fire

• glaciers melt

Air pollution is caused by-

• cutting trees

• building roads

• burning fossil fuels

• strip mining

Which of the following is an example of reusing?

• riding a bicycle

• using solar heat

• recovering aluminum from cans

• cloth diapers

Which of the following human activities helps protect ecosystems?

• using less water

• using chemical fertilizers

• strip mining

• building shopping malls

Why are landfills NOT a perfect solution for disposing of solid wastes?

• They use energy

• They cause acid rain

• They cause pollution

• They use perfectly good land

Why are wetlands important ecosystems?

• They purify water

• They attract endangered animals

• They have been polluted

• They speed up succession

Two examples of climax-community plants are-

• lichens and mosses

• grasses and wildflowers

• hemlock and spruce

• willows and aspens

Which of the following is NOT an example of reclamation?

• constructing an artificial wetland

• growing prairie grasses for lawns

• cleaning up a polluted river

• conserving electricity