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During photosynthesis, plants convert atmospheric carbon into proteins.

Ecosystem pollution can result from both natural events and human actions.

Which of the follow are reactants in a photosynthesis reaction?

None of the above

Oxygen and water

Carbon dioxide and water

Oxygen and glucose

Carbon dioxide and glucose

Which of the following types of biological molecules include the “blueprint” for life?

Phospholipids

Lipids

Carbohydrates

Amino acids

Nucleic acids

What process directly converts atmospheric nitrogen, N2, into a form plants can use?

Sedimentation

Eutrophication

Nitrification

Denitrification

Nitrogen fixation

A pollutant with which of the following characteristics would most likely bioaccumulate in a primary consumer?

None of the above

fatal in very low concentrations

easily broken down in the body

not taken up by plants

degrades slowly in the environment

What is one way that human agriculture affects ecosystems?

None of the above

enhancement of natural stream flow patterns

increased growth of trees

decreased production of pollutants

depletion of soil nutrients

Organisms that are low in marine food chains, such as plankton and shrimp, generally contain very low levels of mercury. Organisms that are higher in the food chains, such as tuna fish and sharks, generally have much higher levels of mercury in their bodies. Which of the following processes best explains this observation?

succession

pollutant cycling

biodegradation

natural selection

biomagnification

Which of the following processes reduces the availability of phosphorus for living things?

decomposition of dead organisms

agricultural runoff

weathering of rock

production of fertilizer

burial of marine skeletons

Which of the following processes removes carbon from the atmosphere?

Cellular respiration in muscle cells

Decomposition of dead organisms

Burning fossil fuels

Cutting down trees

Photosynthesis in ocean plankton

Which of the following elements is required for the formation of nucleic acids and proteins, but not sugars?

None of the above

Hydrogen

Oxygen

Carbon

Nitrogen

Which of the following is an inorganic compound that is part of the nitrogen cycle?

None of the above

methane

glucose

water

ammonia

How do consumers get the nitrogen their bodies need?

consumers do not nitrogen

through the uptake of nitrogen-containing fertilizers

through symbiosis with nitrogen-fixing bacteria

by breathing the nitrogen in the air

by eating other organisms

Living organisms need ____________ because it makes up part of the backbone of DNA molecules and is an important part of cell membranes.

molybdenum

sulfur

oxygen

nitrogen

phosphorus

Which of the following elements is found in all biological molecules?

plutonium

sulfur

nitrogen

phosphorus

carbon

Which of the following processes best explains why an adult fish has a DDT concentration of 2.07 ppm while an osprey has a DDT concentration of 13.80 ppm?

None of the above

bioaccumulation

biodegradation

bioremediation

biomagnification

How is the phosphate made available to plants and animals on Earth?

None of the above

Lightning converts phosphorus into phosphate.

Bacteria convert phosphorus into phosphate.

Plants release phosphorus during photosynthesis.

Weathering releases phosphate into the soil.

A farmer decides to grow peas and soybeans. He plants these two crops in all of his fields. What impact would this have on the nutrients in the soil?

None of the above

There would be a decrease in the amount of nitrate (NO3−).

There would be an increase in the amount of phosphate (PO43−).

There would be an increase in the amount of carbon dioxide (CO2)

There would be an increase in the amount of ammonium (NH4+).

Which organism in the picture on the left would have the highest concentration of PCBs?

The Killer Whale

What do the following processes have in common?- Volcanic Activity- Decomposition- Cellular Respiration

None of the above

They are all part of the nitrogen cycle.

They increase the PO4 in the soil.

They help reduce greenhouse gases.

They all release CO2 into the atmosphere.

Your classmate tells you that all forest fires are bad. Which of the following observations could you use to challenge your classmate’s assumption?

None of the above.

Forest fires threaten human settlements.

Forest fires release carbon dioxide into the environment.

Forest fires destroy bird nests and animal habitats.

Forest fires recycle nutrients and create more diversity in the forest.