Topic 7 Ex 2 Read About It

After a volcanic eruption, new rock forms from ______.

• cooled lava

• eroded soil

• fallen leaves

• decomposed plants

What role do decomposers play in primary succession?

• They build new rocks

• They break down remains to make better soil

• They provide shade

• They produce oxygen

Over time, as more organic material and soil build up, new species such as ______ move into the area.

• fish

• birds

• insects

• mammals

Which of the following is NOT a step in primary succession?

• Formation of new rock

• Growth of pioneer species

• Building of skyscrapers

• Development of a stable ecosystem.

What is secondary succession?

• The initial colonization of barren land

• The series of changes in an ecosystem after a disturbance

• The growth of plants in a desert

• The extinction of species in an area.

Which of the following is NOT a cause of secondary succession?

• A) Tsunamis

• B) Logging

• C) Planting flowers

• D) Tornadoes

Fill in the blank: At the beginning of secondary succession, the variety of species is often ________.

• high

• low

• stable

• extinct

Which type of succession occurs when there is no soil at the start?

• Primary Succession

• Secondary Succession

• Both A and B

• Neither A nor B

Fill in the blank: Primary succession typically begins on surfaces where no _______ exists.

• Water

• Soil

• Air

• Light

Which of the following is a characteristic of primary succession?

• A) Rapid regrowth

• B) Initial absence of soil

• C) High initial biodiversity

• D) Occurs after a forest fire.