What is one of the best ways to represent the

interdependence of all of the organisms in an

ecosystem?

Throughout New York State, some farmers have

switched from growing a variety of vegetable crops to

growing a single crop, such as corn. Other farmers are

concerned that such a practice will make it more

likely that an entire crop could be lost to disease or

infestation by an insect pest. This is a valid concern

because this practice

Stability within an ecosystem is achieved partially by

the presence of organisms that break down important

molecules and make them available for other

organisms to use. These organisms are

The bar graph below shows the number of species in

four pond ecosystems.

Based on this information, which ecosystem is likely

to be the most stable?

Many oak trees are cut down and removed from an

oak-hickory forest. A likely result of the direct

harvesting of the oak species would be the

The diagram below represents an energy pyramid.

Which type of organism could occupy levels B, C,

and D of this energy pyramid?

Which human activity most directly causes a

significant increase in the amount of carbon dioxide

in the atmosphere?

Which row in the chart below represents the most

likely changes in the atmosphere due to widespread

deforestation?

Producers are generally found at the beginning of a

food chain. Which statement best explains why this

is true?

Some organisms in an ecosystem are represented in

the pyramid below. In the pyramid, the arrows

labeled X represent

Base your answer to the question on the diagram

below and on your knowledge of biology. The

diagram represents trophic levels in an ocean

environment. The organisms found at the second

trophic level of this pyramid would be

The chart below represents some of the events that

occur during the cycling of nutrients in an

ecosystem. Which organisms would most

appropriately complete the chart when written in the

circle at X?

An invasive species, the spiny water flea, was

recently found in a New York lake. These water fleas

eat zooplankton, a food also consumed by native

fishes. The fleas spread from lake to lake by

attaching to fishing lines, anchor ropes, and boats.

Which statement best describes the effect of the

water flea on the lake?

Carbon dioxide and oxygen are important resources

in ecosystems and are

Although we rely on coal, oil, and natural gas to

produce energy, some environmental scientists have

proposed that we use less fossil fuel. One reason to

support this proposal is to

For several years now, there has been discussion of

constructing a large oil pipeline across the United

States. Which statement expresses a major concern

many people are likely to have about the proposed

pipeline?