Productivity of an Ecosystem

The diagram shows the amount of phosphorus measured in teragrams (1 teragram = 1×10^12) grams), in the various reservoirs of the phosphorus cycle. Which of the following is the best explanation for why there is such a small amount of phosphorus that moves into aquatic systems?

• Phosphorus is highly stable in the atmosphere and remains there for long periods of time.

• The amount of phosphorus in the cycle has been greatly reduced because of the use of catalytic converters in automobiles.

• There is not a gaseous phase of the phosphorus cycle, and therefore the movement of phosphorus into oceanic reservoirs is very slow.

• The phosphorus cycle occurs so rapidly that it does not exist in any one reservoir for a very long time.

According to the diagram, the movement of phosphorus between biological organisms and soil is in a steady state in an undisturbed system. Which of the following best explains the reason for this steady movement?

• Phosphorus is taken up by plants during photosynthesis to create carbohydrates.

• A decrease in buffer zones prevents phosphorus runoff in waterways.

• There is a rapid influx of phosphorus from the weathering of rocks.

• Readily available organic phosphorus in the soil is assimilated by plants.

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NGSS.MS-LS2-3

Based on the diagram, which of the following reservoirs contains the most phosphorus?

• Plants

• Sediments

• Soil

• Oceans

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NGSS.MS-ESS2-1

NGSS.MS-LS2-3

The diagrams above show an area that was once a pasture that has since undergone changes to the vegetation over time. Which of the following changes in the hydrologic cycle is most likely to occur as a result of the change in vegetation in the area?

• Increased infiltration

• Increased runoff

• Decreased transpiration

• Decreased precipitation

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NGSS.MS-ESS2-4

Which letter correctly identifies the part of the hydrologic cycle that is most directly affected by impervious building materials, such as concrete and asphalt?

• A

• B

• C

• D

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NGSS.MS-ESS2-4

Which letter correctly identifies a process of the hydrologic cycle in which the phase of water is changed from a liquid to a gas?

• A

• B

• C

• D

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NGSS.MS-ESS2-1

NGSS.MS-ESS2-4

Which of the following best describes gross primary productivity in an ecosystem?

• Gross primary productivity is the total amount of energy captured by producers plus the energy used by consumers over time.

• Gross primary productivity is the total amount of energy captured by producers minus the energy that producers respire over time.

• Gross primary productivity is the total amount of energy lost as heat during energy transfer between trophic levels.

• Gross primary productivity is the total amount of solar energy captured by producers through photosynthesis over time.

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NGSS.MS-LS1-6

NGSS.MS-LS2-3

Which of the following best describes the net primary productivity of an ecosystem?

• Net primary productivity is the amount of energy captured by producers through photosynthesis over time.

• Net primary productivity is the amount of energy lost by producers through respiration over time.

• Net primary productivity is the amount of energy lost through respiration by producers subtracted from the gross primary productivity of an ecosystem.

• Net primary productivity is the amount of energy lost through respiration by producers added to the gross primary productivity of an ecosystem.

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NGSS.MS-LS2-3

Scientists calculated the net primary productivity at two different forest sites. Both forests have the same gross primary productivity. Forest A has a net primary productivity of 1,650kcal/m^2/year, and forest B has a net primary productivity of 1,110kcal/m^2/year. Which of the following statements is best supported by the data?

• Forest A has a higher rate of decomposition by bacteria than forest B.

• Forest A has more biodiversity than forest B.

• Forest A producers have lower rates of cellular respiration than forest B producers.

• Forest A producers have more biomass than forest B producers.

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NGSS.HS-LS2-3

NGSS.HS-LS2-4

Which of the following best describes the movement of energy in an ecosystem?

• Energy is constantly recycled by decomposers for use by producers.

• Energy is harnessed by producers, and available energy decreases with each trophic level transfer.

• Energy is absorbed by plants through water and soil and then moves up the food chain through consumers.

• Energy is magnified as it moves up the trophic levels, and tertiary consumers store the most energy in a food web.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3