Use the diagram of the marine food web below to answer the following.

How would the food web be affected if the phytoplankton were removed?

Use the diagram of the marine food web below to answer the following.

Cod is a popular fish in the human diet. If too many cod were removed due to overfishing, which of these would most likely occur?

Use the information and the food web below to answer the following.

A marine environment provides a habitat for a variety of plants and animals. A small part of a marine food web is shown below.

Horseshoe crabs are used by fisherman for bait. If the horseshoe crab population were reduced by overfishing, which of these groups of organisms would most likely decrease in number?

The pesticide DDT was used to kill mosquitoes for many years. DDT entered bodies of water, moved up the food chain, and built up in the tissues of fish. When female bald eagles ate these fish, they produced eggs with very thin shells. The eggs broke when the eagles sat on their nests. The U.S. government banned the use of DDT in 1972.

Which of these graphs most likely shows how the ban of DDT affected the bald eagle population?
 

The energy pyramid below shows the flow of energy through the organisms in a kelp forest ecosystem in the Pacific Ocean. Use the energy pyramid to answer the following.

How would the populations of other organisms in the energy pyramid be affected if the population of sea urchins suddenly decreased?

Scientists estimate that 200 non-native organisms have been introduced into Chesapeake Bay. Which of these statements is not true about non-native organisms?

Rain forests are often cleared to provide land for farming. Which of these outcomes is the most immediate effect of this practice on the global environment?

Black skimmers are water birds that live along coastal beaches, bays, estuaries, and marshes. They fly just above the surface of the water using their lower jaw to catch small fish, shrimp, and other small crustaceans.

These birds nest in simple, unlined depressions in the sand. Scientists have observed a decline in the number of nests. Some causes of this decline include a lack of suitable nesting sites, beach erosion, and human disturbances.

When people approach their nests, the birds become aggressive and chase away intruders. Other animals, like crows, will take advantage of the unprotected nests and feed on the eggs.

A continued decrease in black skimmer populations will most likely lead to

Use the information below to answer the following question.

A scientist wanted to find out if low numbers of fish found in a nearby lake were related to acid rain. During his three-year study, he analyzed rainwater and lake water samples. By gathering samples of fish, he estimated the number of fish in the lake.

Each year he found that both the rainwater and lake water became more acidic, and the number of fish decreased.

His data suggested that acid rain may be responsible for the decrease in the number of fish found in the lake.

What most likely led to the rainwater’s increasing acidity?

The populations of wolves and other large predators have decreased throughout the United States. This disruption of the natural food web will most likely lead to

The use of certain chemicals by humans has caused holes to form in the Earth’s ozone layer. This allows more ultraviolet (UV) light to reach the oceans. Scientists are concerned that an increase in UV light will start killing microscopic marine algae.

Which of these statements describes how the ocean food web would be affected by a large decrease in microscopic marine algae?

Use the technical passage to answer the following item.

Recent increases in bear-human interactions in the westernmost part of Maryland are causing serious problems. Which of these is the most likely cause for this increased interaction?

An increase in the use of fossil fuels has increased the amount of sulfur compounds in Earth’s atmosphere. Which of these is a direct result of the increased amount of sulfur in the atmosphere?