Organisms and Environment

The more diverse an ecosystem is...

• the more threatened its populations are.

• the more similar the species will be.

• the more stable it is.

• the fewer varieties of species are present.

Where are you most likely to find the greatest variety and numbers of animal life?

• On a newly mowed lawn

• Close to a pond with rocks, water, and several types of plants

• In a pond, a few meters away from the water's edge

• Next to a paved surface

A plant with broad, flat leaves is best adapted for...

• conserving heat in a tundra.

• collecting water in a desert.

• avoiding insects in a prairie.

• absorbing light in a rainforest.

How does secondary succession help restore equilibrium to a region destroyed by a flood?

• It increases the number and types of species.

• It brings back species from extinction.

• It stops other floods from occurring.

• It decreases the rate of evolution.

Which of the following situations contributes to the sustainability of an ecosystem?

• Increase in biodiversity

• Decrease in biodiversity

• Extinction of a population from the ecosystem

• Removal of many populations of organisms

Which of the following sequences most likely represents ecological succession on a recently abandoned wheat field?

• Grasses --> Flowering Plants --> Shrubs --> Native Trees

• Native Trees --> Shrubs --> Flowering Plants --> Grasses

• Shrubs --> Grasses --> Native Trees --> Flowering Plants

• Flowering Plants --> Native Trees --> Shrubs --> Grasses

Which statement below best describes how biodiversity contributes to the sustainability of an ecosystem?

• A variety of plant and animal species allows for more survivors of a natural disaster.

• Having more species in an ecosystem allows the human population to increase in size.

• Low biodiversity reduces the competition for resources, which helps native species survive.

• Fewer species in the ecosystem reduces the likelihood that disease spreads through the ecosystem.

A hurricane hits a coastal prairie and destroys the habitat. Years later there is an appearance of small plants with rapidly spreading roots.

This vegetation describes...

• a microhabitat.

• primary succession.

• secondary succession.

• biodiversity.

A flower bed is created at a school so flowers can be planted in the autumn.

Over the summer, the flower bed is ignored. Which of the following should the students expect to find when they come back to school?

• 
• 
• 
• 

Which event would most likely cause an ecosystem to have the lowest biodiversity 3 years later?

• Clearing land for a highway.

• A river floods a cornfield.

• A forest fire destroys the plant growth.

• A lava flow creates a new section of land.