Unit 7 Exam

Coral reefs are found in coastal ecosystems. Coral reefs have a high biodiversity. Which statement is true about coral reefs?

• Matter and energy are not easily passed throughout a coral reef.

• Coral reefs usually contain only a few different types of fish and coral.

• Coral reefs would not be able to recover from an ecosystem disturbance.

• There are many different species of plants and animals found on a coral reef.

Which of these is not an accurate statement about ecosystem health?

• A healthy Ecosystem has high biodiversity.

• Ecosystems in good health limit pests with natural predators.

• A healthy ecosystem can buffer the impact of storms and limits the spread of disease.

• Humans can benefit from healthy ecosystems but have little impact on ecosystem health.

Which of these describes a way in which humans could increase biodiversity in a marine ecosystem?

• They could introduce new species to the ecosystem.

• The could limit fishing to only one kind of fish in the ecosystem.

• They could ban boating, snorkeling, and scuba diving in the ecosystem.

• They could restrict the amount of each type of fish or shellfish harvested from the ecosystem.

Which of these characteristics is often used as a measure of an ecosystem's health?

• The variety of species that live there.

• The number of people who live there.

• The amount of pollution that occurs there.

• The types of activities that can be done there.

Some grass species need fire in order for their seems to germinate. Why might this adaptation be useful for grasses

• Fire allows trees to grow and to provide shade for the grasses.

• The hot temperature of the fire helps the grasses grow faster.

• Seeds can germinate in an area that has been cleared by a fire.

• Fire discourages grazing by large animals so the grasses can grow higher.

Which statement best describes ecosystems?

• They can never change once they are established.

• They constantly change in different ways over time.

• Ecosystems always revert back to their original state.

• Each ecosystem can exist for only a specific length of time.

Which of these might result from the process of natural eutrophication.

• A pond becomes a meadow.

• A rock breaks down into soil.

• A glacier retreats to expose new land.

• A nonnative species takes resources from native species.

What is the first step in eutrophication of a pond?

• A meadow develops

• Plant communities take over.

• Excess nutrients build up in the water.

• Debris builds up on the bottom of the pond.

Which of these support the statement that we must protect diversity because it affects the amount of resources we can use sustainably?

• Biodiversity decreases ecosystem productivity because different species use resources in different ways.

• A greater number of only a few species increases ecosystem resiliency and an ecosystem's ability to resist disturbance.

• A variety of many different species increases ecosystem health by concentrating human-made toxins and poisons in water.

• Biodiversity maintains ecosystem health by recycling and storing nutrients, maintaining water quality, and stabilizing climate.

A politician is trying to remove a dam on a local river. Some people oppose the removal saying the dam removal will cost too much money. What is one argument the politician could use to get people to support the project in spite of its costs?

• Removing the dam will help form new reservior.

• Removing the dam will force the ricer to follow a controlled path.

• Removing the dam will help the water in the river flow at a more constant rate.

• Removing the dam will allow fish to reach their natural breeding grounds upstream of the dam site.